Podcasts about gravitational lensing

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Best podcasts about gravitational lensing

Latest podcast episodes about gravitational lensing

StarTalk Radio
Einstein's Crumbs with Janna Levin

StarTalk Radio

Play Episode Listen Later Apr 29, 2025 52:17


How did Einstein's work influence the world we know today? Neil deGrasse Tyson and  Harrison Greenbaum team up with astrophysicist Janna Levin, PhD, to explore Einstein's physics and its resulting discoveries, from Walmart laser pointers to black holes and wormholes. NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here:https://startalkmedia.com/show/einsteins-crumbs-with-janna-levin/Thanks to our Patrons Vickie Patik, Chukwuma, Jaxie Thund-a-Lund, Eric Muldoon, Kevin Price, True Gordon, Chris Del Rosario, Bill Taylor, Garth Graham, George Koris, Kari Legates, Robert Browning, Everyone wants to be a cat, Christine Ferguson, Monte Plays Games, Bernard Pang, HARMS, Ari Nahmad, Alyssa Feldhaus, Noel Aguilar, 5ityf, Lez Dunn, Jeff Blessing, Brian Hann, Gregory Rodgers, Renzo, Serge, Ralph Loizzo, Tejas Phatak, André Shabazian, Lester W Marlatt, WILLIAM WALKER, Prema Wargo, Gaz Davies, Shota Dzidziguri, Phillippe Chicoineau, Hunter Hall, Marcos Lima, Mark S. Jones, Robert Fisher, Dave Zetrenne, Moad, Brain Jones, Sergio, Jeff Sauer, Donald G Smith, and Aleksey Parsetich for supporting us this week. Subscribe to SiriusXM Podcasts+ to listen to new episodes of StarTalk Radio ad-free and a whole week early.Start a free trial now on Apple Podcasts or by visiting siriusxm.com/podcastsplus.

Lehto Files - Investigating UAPs
Zero Point Energy Unveiled UFO Technology with Lehto & Forbes

Lehto Files - Investigating UAPs

Play Episode Listen Later Jan 20, 2025 105:34


explore the groundbreaking intersection of zero-point energy, UFO technology, and advanced physics with Chris Lehto and Ashton Forbes. Dive into the secrets of suppressed science, the future of free energy, and how these innovations could reshape humanity's understanding of the universe. This engaging discussion examines anti-gravity propulsion, the electric universe, and what full disclosure might mean for our world. Thanks for watching, liking, and subscribing! It really helps the channel.Check out Ashton's Youtube Channel here for more great content: https://www.youtube.com/@UCHmFQzkpaJBSDD1PPFhPPSgSupport the channel and get exclusive content at https://www.patreon.com/chrislehtoJoin this channel on YouTube to get access to the perks: https://www.youtube.com/channel/UCVNKdkLzWuy1oLuCuCv4NCA/joinContinue the Discussion on Lehto Files Discord here: https://discord.gg/uap-society-813850576718397470get access to all LehtoFiles links here: https://linktr.ee/chrislehto Follow Chris on X: @LehtoFiles Lehto Files is now on Instagram: https://www.instagram.com/lehto_files/reels/Invest in UAP Society NFTs! Each UAPSociety NFT grants early/ad-free access to all LehtoFiles videos- https://opensea.io/collection/uapeezDonate eth to: chrislehto.eth full ETH address is 0x26E3c9b2A5E5b6B7FB54f5F0120B0E4840EB7B24Sharing my referral link for when you order your Tesla. You'll get 500 € off the purchase of a Tesla product. https://www.tesla.com/referral/christopher3910500:00 Ashton Forbes - Science is the Key 10:00 Zero Point Energy is the Aether 18:58 Gravitational Lensing is UAP Signature 31:38 How does Zero Point Energy Work? 43:01 Should this Tech be released? 55:36 Fractal Universe Theory 1:07:59 Ontological Shock 1:18:51 Aether is already proven 1:29:37 LIGO and Gravity Waves 1:38:08 Livelsberger Cybertruck UAP USAPBecome a supporter of this podcast: https://www.spreaker.com/podcast/lehto-files-investigating-uaps--5990774/support.

StarTalk Radio
Time and The Universe, with Charles Liu

StarTalk Radio

Play Episode Listen Later Sep 27, 2024 46:33


Can time itself die? Astrophysicist Charles Liu is back in the hosting hot seat alongside comic co-host Chuck Nice to explore black holes, big bangs, our understanding of time and how it relates to the universe. NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here: https://startalkmedia.com/show/time-and-the-universe-with-charles-liu/x(Originally Aired December 18, 2018) Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

ITSPmagazine | Technology. Cybersecurity. Society
The Gift of Gravitational Lensing | A Conversation with Dr. Slava Turyshev | Stories From Space Podcast With Matthew S Williams

ITSPmagazine | Technology. Cybersecurity. Society

Play Episode Listen Later Apr 27, 2024 51:01


Guest | Dr. Slava Turyshev, Research Scientist NASA Jet Propulsion Laboratory [@NASAJPL]On LinkedIn | https://www.linkedin.com/in/slava-g-turyshev-62b88/On Facebook | https://www.facebook.com/turyshevHost | Matthew S WilliamsOn ITSPmagazine  

Stories From Space
The Gift of Gravitational Lensing | A Conversation with Dr. Slava Turyshev | Stories From Space Podcast With Matthew S Williams

Stories From Space

Play Episode Listen Later Apr 27, 2024 51:01


Guest | Dr. Slava Turyshev, Research Scientist NASA Jet Propulsion Laboratory [@NASAJPL]On LinkedIn | https://www.linkedin.com/in/slava-g-turyshev-62b88/On Facebook | https://www.facebook.com/turyshevHost | Matthew S WilliamsOn ITSPmagazine  

Silicon Valley Astronomy Lectures
Black Holes and the Technology to Find Them

Silicon Valley Astronomy Lectures

Play Episode Listen Later Apr 10, 2024 62:42


A Non-technical Talk by Dr. Jessica Lu (University of California, Berkeley) on March 13, 2024The population of black holes, objects left over from dead stars,  is almost entirely unexplored. Only about two dozen black holes are confidently known in our Galaxy. As a result, some of the most basic properties of black holes remain unknown, including the true number of black holes in the Galaxy, their masses and sizes, and how the black holes were formed.  Dr. Lu discusses how she and other astronomers are using "gravitational lensing" -- something predicted by Einstein's work -- to open a new window onto black holes, and how the first free-floating black holes are now being discovered.  She explains, in everyday language, why astronomers expect that the number of known black holes will increase by a factor of 100 over the next decade.

Universe Today Podcast
[Q&A] Supernova VS Nova, Orientation of the Moon, Gravitational Lensing of the CMB

Universe Today Podcast

Play Episode Listen Later Apr 2, 2024


Does gravitational lensing affect the CMB? Can the Great Attractor solve the Hubble tension? Why don't we put a Deep Space Network antenna in space? What's the difference between a nova and a supernova? Answering all these questions and more in this week's Q&A show.

Universe Today Podcast
[Q&A] Supernova VS Nova, Orientation of the Moon, Gravitational Lensing of the CMB

Universe Today Podcast

Play Episode Listen Later Apr 2, 2024 44:19


Does gravitational lensing affect the CMB? Can the Great Attractor solve the Hubble tension? Why don't we put a Deep Space Network antenna in space? What's the difference between a nova and a supernova? Answering all these questions and more in this week's Q&A show.

Creative Peacemeal
Xiaosheng Huang, Astrophysicist discusses his fascinating field, Einstein, creativity and beauty in science, and more

Creative Peacemeal

Play Episode Listen Later Mar 4, 2024 47:46


Dr. Huang is an Associate Professor at the University of San Francisco. His areas of research include: High Redshift (Faraway) Type Ia Supernovae (SN e Ia), Nearby SN e Ia, and Gravitational Lensing.We chat about the fascinating field, the logistics of becoming an astrophysicist, the beauty of the Universe, our shared love of Einstein and Mozart, and so much more. Visit the Self-Care Institute at https://www.selfcareinstitute.com/ Support the showVisit www.creativepeacemeal.com to leave a review, fan voicemail, and more!Insta @creative_peacemeal_podcastFB @creativepeacemealpodBonfire https://www.bonfire.com/store/creative-peacemeal/Redbubble CPPodcast.redbubble.comCreative Peacemeal READING list here Donate to AhHa!Broadway here! Donate Dachshund Rescue of Houston here Interested in the Self-Care Institute with Dr. Ami Kunimura? Click here Interested in Corrie Legge's content planner? Click here to order! Looking for custom orthotics? Foot and Shoe Solutions is your answer. Click here for more.

Easy Physics
Gravitational Lensing

Easy Physics

Play Episode Listen Later Nov 11, 2023 7:33


Get a monthly subscription to access premium episodes!'Easy Physics' is a podcast that delves into the bizarre and fascinating world of this amazing science. Join us as we use humor and plain language to explore many fundamental principles, and learn about each one of them in a few minutes. From particles that exist in multiple places at once to the immensity of the cosmos, we'll take a lighthearted look at the most mind-bending concepts in physics.Note: This podcast is written and spoken by AI Hosted on Acast. See acast.com/privacy for more information.

StarTalk Radio
The Dark Universe: Exploring the Euclid Mission with Jason Rhodes

StarTalk Radio

Play Episode Listen Later Oct 3, 2023 46:37


What are dark energy and dark matter? Neil deGrasse Tyson and comedian Chuck Nice learn about the Euclid Mission and our latest efforts to uncover the secrets of The Dark Universe with JPL Researcher, Jason Rhodes. NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here:https://startalkmedia.com/show/the-dark-universe-exploring-the-euclid-mission-with-jason-rhodes/Thanks to our Patrons Florian Mueller, Bartek Moryc, Lorena Pereira, Leon Helmink, Stephan Marty, sam jones, and Phillip Berryhill for supporting us this week.Photo Credit: ESA. Acknowledgement: Work performed by ATG under contract for ESA., CC BY-SA IGO 3.0, CC BY-SA 3.0 IGO

System76 Transmission Log
Exploring Astrophysics with the System76 Lemur Pro

System76 Transmission Log

Play Episode Listen Later Sep 20, 2023 35:21


Listen to the latest on System76 computers, manufacturing, and Pop!_OS.This episode welcomes guest Massimo Pascale from UC Berkeley to discuss his work and research around the sunburst arc, super star clusters and Nitrogen-enriched Nebula. Learn how the Lemur Pro and open source software powers some of his research.Check out what we make!Blog: blog.system76.comLaptops: s76.co/WuEDOnoSDesktops: s76.co/Zn4NXTf9Pop!_OS: s76.co/D_IWRvWDShare what you make with us!twitter.com/system76facebook.com/system76instagram.com/system76_com

StarTalk Radio
Cosmic Queries – Black Hole Paradox with Matt O'Dowd

StarTalk Radio

Play Episode Listen Later Jun 13, 2023 54:02


Can we use gravitational lensing to view distant planets? Neil deGrasse Tyson and comedian Chuck Nice explore black holes, quasars, entropy, and more with astrophysicist and host of PBS Space Time, Matt O'Dowd.NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free.Thanks to our Patrons Kelly Madison, Shaun Moats, Vascked, Irene Campbell, Joseph Brown, and Guillermo Leal for supporting us this week.Photo Credit: NOIRLab/NSF/AURA/J. da Silva, CC BY 4.0, via Wikimedia Commons

Serious Inquiries Only
SIO360: How Gravitational Lensing Helps Us Understand the Universe

Serious Inquiries Only

Play Episode Listen Later May 9, 2023 70:07


Dr. Bryan Gillis is back! This time he's here to teach us about gravitational lensing. And along the way, we learn about dark matter and dark energy! What the hell are they? What the hell aren't they? Could you have a black hole made out of dark matter? So much fascinating stuff! Links: ESA Euclid Page, Euclid Wikipedia page, Vimeo Channel for the Royal Observatory.

Astro arXiv | all categories
PERISTOLE: PackagE that geneRates tIme delay plotS caused by graviTatiOnaL lEnsing

Astro arXiv | all categories

Play Episode Listen Later Nov 30, 2022 0:36


PERISTOLE: PackagE that geneRates tIme delay plotS caused by graviTatiOnaL lEnsing by T. S. Sachin Venkatesh et al. on Wednesday 30 November We present PERISTOLE to study the various time delays associated with the pulsar rotation and other general relativistic aspects of binary pulsars. It is made available as an open-source python package which takes some parameters of the double pulsar system as input and outputs the rotational and latitudinal lensing delays along with the geometric and Shapiro delays that arise due to gravitational lensing. This package was intended to provide a way to quickly analyse, evaluate and study the differences between variations of the same systems and also to quantify the consequences that different parameters have over the system. Through this research note, we briefly describe the motivation behind PERISTOLE and showcase its capabilities using the only double pulsar system ever found, J0737-3039. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16036v1

Astro arXiv | all categories
Line-of-sight effects in strong gravitational lensing

Astro arXiv | all categories

Play Episode Listen Later Nov 30, 2022 0:48


Line-of-sight effects in strong gravitational lensing by Pierre Fleury et al. on Wednesday 30 November While most strong-gravitational-lensing systems may be roughly modelled by a single massive object between the source and the observer, in the details all the structures near the light path contribute to the observed images. These additional contributions, known as line-of-sight effects, are non-negligible in practice. This article proposes a new theoretical framework to model the line-of-sight effects, together with very promising applications at the interface of weak and strong lensing. Our approach relies on the dominant-lens approximation, where one deflector is treated as the main lens while the others are treated as perturbations. The resulting framework is technically simpler to handle than the multi-plane lensing formalism, while allowing one to consistently model any sub-critical perturbation. In particular, it is not limited to the usual external-convergence and external-shear parameterisation. As a first application, we identify a specific notion of line-of-sight shear that is not degenerate with the ellipticity of the main lens, and which could thus be extracted from strong-lensing images. This result supports and improves the recent proposal that Einstein rings might be powerful probes of cosmic shear. As a second application, we investigate the distortions of strong-lensing critical curves under line-of-sight effects, and more particularly their correlations across the sky. We find that such correlations may be used to probe, not only the large-scale structure of the Universe, but also the dark-matter halo profiles of strong lenses. This last possibility would be a key asset to improve the accuracy of the measurement of the Hubble-Lema^itre constant via time-delay cosmography. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2104.08883v5

Astro arXiv | all categories
PERISTOLE: PackagE that geneRates tIme delay plotS caused by graviTatiOnaL lEnsing

Astro arXiv | all categories

Play Episode Listen Later Nov 29, 2022 0:36


PERISTOLE: PackagE that geneRates tIme delay plotS caused by graviTatiOnaL lEnsing by T. S. Sachin Venkatesh et al. on Tuesday 29 November We present PERISTOLE to study the various time delays associated with the pulsar rotation and other general relativistic aspects of binary pulsars. It is made available as an open-source python package which takes some parameters of the double pulsar system as input and outputs the rotational and latitudinal lensing delays along with the geometric and Shapiro delays that arise due to gravitational lensing. This package was intended to provide a way to quickly analyse, evaluate and study the differences between variations of the same systems and also to quantify the consequences that different parameters have over the system. Through this research note, we briefly describe the motivation behind PERISTOLE and showcase its capabilities using the only double pulsar system ever found, J0737-3039. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16036v1

Astro arXiv | all categories
Etherington duality breaking: gravitational lensing in non-metric spacetimes versus intrinsic alignments

Astro arXiv | all categories

Play Episode Listen Later Nov 23, 2022 0:53


Etherington duality breaking: gravitational lensing in non-metric spacetimes versus intrinsic alignments by Eileen Sophie Giesel et al. on Wednesday 23 November The Etherington distance duality relation is well-established for metric theories of gravity, and confirms the duality between the luminosity distance and the angular diameter distance through the conservation of surface brightness. A violation of the Etherington distance duality due to lensing in a non-metric spacetime would lead to fluctuations in surface brightness of galaxies. Likewise, fluctuations of the surface brightness can arise in classical astrophysics as a consequence of intrinsic tidal interaction of galaxies with their environment. Therefore, we study these in two cases in detail: Firstly, for intrinsic size fluctuations and the resulting changes in surface brightness, and secondly, for an area-metric spacetime as an example of a non-metric spacetime where the distance duality relation itself acquires modifications. The aim of this work is to quantify whether a surface brightness fluctuation effect due to area-metric gravity would be resolvable compared to the similar effect caused by intrinsic alignment. We thus compare the auto- and cross-correlations of the angular spectra in these two cases and show that the fluctuations in intrinsic brightness can potentially be measured with a cumulative signal-to-noise ratio $Sigma(ell) geq 3$ in a Euclid-like survey. The measurement in area-metric spacetimes, however, depends on the specific parameter choices, which also determine the shape and amplitude of the spectra. While lensing surveys do have sensitivity to lensing-induced surface brightness fluctuations in area-metric spacetimes, the measurement does not seem to be possible for natural values of the Etherington-breaking parameters. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2208.07197v2

Astro arXiv | all categories
Etherington duality breaking: gravitational lensing in non-metric spacetimes versus intrinsic alignments

Astro arXiv | all categories

Play Episode Listen Later Nov 22, 2022 0:53


Etherington duality breaking: gravitational lensing in non-metric spacetimes versus intrinsic alignments by Eileen Sophie Giesel et al. on Tuesday 22 November The Etherington distance duality relation is well-established for metric theories of gravity, and confirms the duality between the luminosity distance and the angular diameter distance through the conservation of surface brightness. A violation of the Etherington distance duality due to lensing in a non-metric spacetime would lead to fluctuations in surface brightness of galaxies. Likewise, fluctuations of the surface brightness can arise in classical astrophysics as a consequence of intrinsic tidal interaction of galaxies with their environment. Therefore, we study these in two cases in detail: Firstly, for intrinsic size fluctuations and the resulting changes in surface brightness, and secondly, for an area-metric spacetime as an example of a non-metric spacetime where the distance duality relation itself acquires modifications. The aim of this work is to quantify whether a surface brightness fluctuation effect due to area-metric gravity would be resolvable compared to the similar effect caused by intrinsic alignment. We thus compare the auto- and cross-correlations of the angular spectra in these two cases and show that the fluctuations in intrinsic brightness can potentially be measured with a cumulative signal-to-noise ratio $Sigma(ell) geq 3$ in a Euclid-like survey. The measurement in area-metric spacetimes, however, depends on the specific parameter choices, which also determine the shape and amplitude of the spectra. While lensing surveys do have sensitivity to lensing-induced surface brightness fluctuations in area-metric spacetimes, the measurement does not seem to be possible for natural values of the Etherington-breaking parameters. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2208.07197v2

Astro arXiv | all categories
The Effect of Gravitational Lensing on Fast Transient Event Rates

Astro arXiv | all categories

Play Episode Listen Later Oct 18, 2022 0:38


The Effect of Gravitational Lensing on Fast Transient Event Rates by Mawson W. Sammons et al. on Tuesday 18 October Fast cosmological transients such as fast radio bursts (FRBs) and gamma-ray bursts (GRBs) represent a class of sources more compact than any other cosmological object. As such they are sensitive to significant magnification via gravitational lensing from a class of lenses which are not well-constrained by observations today. Low-mass primordial black holes are one such candidate which may constitute a significant fraction of the Universe's dark matter. Current observations only constrain their density in the nearby Universe, giving fast transients from cosmological distances the potential to form complementary constraints. Motivated by this, we calculate the effect that gravitational lensing from a cosmological distribution of compact objects would have on the observed rates of FRBs and GRBs. For static lensing geometries, we rule out the prospect that all FRBs are gravitationally lensed for a range of lens masses and show that lens masses greater than $10^{-5}M_odot$ can be constrained with 8000 un-localised high fluence FRBs at 1.4GHz, as might be detected by the next generation of FRB-finding telescopes. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.09487v1

Astro arXiv | all categories
BICEP Keck XVII: Line of Sight Distortion Analysis: Estimates of Gravitational Lensing, Anisotropic Cosmic Birefringence, Patchy Reionization, and Systematic Errors

Astro arXiv | all categories

Play Episode Listen Later Oct 17, 2022 0:51


BICEP Keck XVII: Line of Sight Distortion Analysis: Estimates of Gravitational Lensing, Anisotropic Cosmic Birefringence, Patchy Reionization, and Systematic Errors by BICEP/Keck Collaboration et al. on Monday 17 October We present estimates of line-of-sight distortion fields derived from the 95 GHz and 150 GHz data taken by BICEP2, BICEP3, and Keck Array up to the 2018 observing season, leading to cosmological constraints and a study of instrumental and astrophysical systematics. Cosmological constraints are derived from three of the distortion fields concerning gravitational lensing from large-scale structure, polarization rotation from magnetic fields or an axion-like field, and the screening effect of patchy reionization. We measure an amplitude of the lensing power spectrum $A_L^{phiphi}=0.95 pm 0.20$. We constrain polarization rotation, expressed as the coupling constant of a Chern-Simons electromagnetic term $g_{agamma} leq 2.6 times 10^{-2}/H_I$, where $H_I$ is the inflationary Hubble parameter, and an amplitude of primordial magnetic fields smoothed over 1 Mpc $B_{1text{Mpc}} leq 6.6 ;text{nG}$ at 95 GHz. We constrain the root mean square of optical-depth fluctuations in a simple "crinkly surface" model of patchy reionization, finding $A^tau

Astro arXiv | all categories
The spherical Fast Multipole Method sFMM for Gravitational Lensing Simulation

Astro arXiv | all categories

Play Episode Listen Later Oct 16, 2022 0:38


The spherical Fast Multipole Method sFMM for Gravitational Lensing Simulation by Xingpao Suo et al. on Sunday 16 October In this paper, we present a spherical Fast Multipole Method (sFMM) for ray tracing simulation of gravitational lensing (GL) on a curved sky. The sFMM is a non-trivial extension of the Fast Multiple Method (FMM) to sphere $mathbb S^2$, and it can accurately solve the Poisson equation with time complexity of $O(N)log(N)$, where $N$ is the number of particles. It is found that the time complexity of the sFMM is near $O(N)$ and the computational accuracy can reach $10^{-10}$ in our test. In addition, compared with the Fast Spherical Harmonic Transform (FSHT), the sFMM is not only faster but more accurate, as it has the ability to reserve high-frequency components of the density field. These merits make the sFMM an optimum method to simulate the gravitational lensing on a curved sky, which is the case for upcoming large-area sky surveys, such as the Vera Rubin Observatory and the China Space Station Telescope. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.07021v2

Astro arXiv | all categories
The spherical Fast Multipole Method sFMM for Gravitational Lensing Simulation

Astro arXiv | all categories

Play Episode Listen Later Oct 13, 2022 0:34


The spherical Fast Multipole Method sFMM for Gravitational Lensing Simulation by Xingpao Suo et al. on Thursday 13 October In this paper, we present a spherical Fast Multipole Method (sFMM) for ray tracing simulation of gravitational lensing (GL) on a curved sky. The sFMM is a non-trivial extension of the Fast Multiple Method (FMM) to sphere $mathbb S^2$, and it can accurately solve the Poisson equation with time complexity of $O(N)log(N)$, where $N$ is the number of particles. It is found that the time complexity of the sFMM is near $O(N)$ and the computational accuracy can reach $10^{-10}$ in our test. In addition, comparing with the Fast Spherical Harmonic Transform (FSHT), the sFMM is not only faster but more accurate, as it has the ability to reserve high frequency component of the density field. These merits make the sFMM an optimum method to simulation the gravitational lensing on a curved sky, which is the case for upcoming large-area sky surveys, such as the Vera Rubin Observatory and the China Space Station Telescope. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.07021v1

Astro arXiv | all categories
Gravitational lensing of pulsars as a probe of dark matter halos

Astro arXiv | all categories

Play Episode Listen Later Oct 12, 2022 1:00


Gravitational lensing of pulsars as a probe of dark matter halos by Francesca von Braun-Bates. on Wednesday 12 October A particular open problem in cosmology is whether dark matter on small scales is clumpy, forming gravitationally-bound halos distributed within the Galaxy. The practical difficulties inherent in testing this hypothesis stem from the fact that, on astrophysical scales, dark matter is solely observable via its gravitational interaction with other objects. This thesis presents a gravitational-lensing-based solution for the mapping and characterisation of low-mass, dark matter halos via their signature in millisecond pulsar observations. This involves: first, determining the time delay and magnification surfaces generated in the frame of reference of the halo; second, obtaining the corresponding pulsar signature in the reference frame of the observer; and last, generalising the method to multiple halos at varying distances. We discuss whether the delay is observationally detectable for both single and multiple lenses. The key dependency of the time delay is the density profile adopted for the halo. I utilise a variety of proposed halo mass profiles -- elliptical, Schwarzschild, horizontal-disc lenses and the Navarro-Frenk-White (NFW) density profile -- which are applicable over a broad range of halo masses. I demonstrate the use of Hankel transforms to increase the efficiency of the relativistic time delay calculation. The observational signatures of such halos are best identified using millisecond pulsars due to their high rotational frequencies and period stability. My method does not require major adjustments when searching for signs of lensing, thus it is unnecessary to implement specialist data reduction pipelines. Thus we can leverage data from both existing and future surveys easily. This method is readily extensible to nearby globular clusters and galaxies, pending improvements in pulsar detection at such distances. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.06151v1

Astro arXiv | all categories
Strong Gravitational Lensing Parameter Estimation with Vision Transformer

Astro arXiv | all categories

Play Episode Listen Later Oct 10, 2022 0:39


Strong Gravitational Lensing Parameter Estimation with Vision Transformer by Kuan-Wei Huang et al. on Monday 10 October Quantifying the parameters and corresponding uncertainties of hundreds of strongly lensed quasar systems holds the key to resolving one of the most important scientific questions: the Hubble constant ($H_{0}$) tension. The commonly used Markov chain Monte Carlo (MCMC) method has been too time-consuming to achieve this goal, yet recent work has shown that convolution neural networks (CNNs) can be an alternative with seven orders of magnitude improvement in speed. With 31,200 simulated strongly lensed quasar images, we explore the usage of Vision Transformer (ViT) for simulated strong gravitational lensing for the first time. We show that ViT could reach competitive results compared with CNNs, and is specifically good at some lensing parameters, including the most important mass-related parameters such as the center of lens $theta_{1}$ and $theta_{2}$, the ellipticities $e_1$ and $e_2$, and the radial power-law slope $gamma'$. With this promising preliminary result, we believe the ViT (or attention-based) network architecture can be an important tool for strong lensing science for the next generation of surveys. The open source of our code and data is in url{https://github.com/kuanweih/strong_lensing_vit_resnet}. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.04143v1

Astro arXiv | all categories
Combining gravitational lensing and gravitational redshift to measure the anisotropic stress with future galaxy surveys

Astro arXiv | all categories

Play Episode Listen Later Sep 19, 2022 0:46


Combining gravitational lensing and gravitational redshift to measure the anisotropic stress with future galaxy surveys by Isaac Tutusaus et al. on Monday 19 September Galaxy surveys provide one of the best ways to constrain the theory of gravity at cosmological scales. They can be used to constrain the two gravitational potentials encoding time, $Psi$, and spatial, $Phi$, distortions, which are exactly equal at late time within General Relativity. Hence, any small variation leading to a non-zero anisotropic stress, i.e. a difference between these potentials, would be an indication for modified gravity. Current analyses usually consider gravitational lensing and redshift-space distortions to constrain the anisotropic stress, but these rely on certain assumptions like the validity of the weak equivalence principle, and a specific time evolution of the functions encoding deviations from General Relativity. In this work, we propose a reparametrization of the gravitational lensing observable, together with the use of the relativistic dipole of the correlation function of galaxies to directly measure the anisotropic stress with a minimum amount of assumptions. We consider the future Legacy Survey of Space and Time of the Vera C. Observatory and the future Square Kilometer Array, and show that combining gravitational lensing and gravitational redshift with the proposed approach we will achieve model-independent constraints on the anisotropic stress at the level of $sim 20,%$. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.08987v1

Astro arXiv | all categories
Weak Gravitational Lensing Shear Estimation with Metacalibration for the Roman High-Latitude Imaging Survey

Astro arXiv | all categories

Play Episode Listen Later Sep 14, 2022 0:17


Weak Gravitational Lensing Shear Estimation with Metacalibration for the Roman High-Latitude Imaging Survey by Masaya Yamamoto et al. on Wednesday 14 September We investigate the performance of the Metacalibration shear calibration framework using simulated imaging data for the Nancy Grace Roman Space Telescope (Roman) reference High-Latitude Imaging Survey (HLIS). The weak lensing program of the Roman mission requires the mean weak lensing shear estimate to be calibrated within about 0.03%. To reach this goal, we can test our calibration process with various simulations and ultimately isolate the sources of residual shear biases in order to improve our methods. In this work, we build on the Roman HLIS image simulation pipeline in Troxel et al. 2021 to incorporate several new realistic processing-pipeline updates necessary to more accurately process the imaging data and calibrate the shear. We show the first results of this calibration for six deg$^2$ of the simulated reference HLIS using Metacalibration and compare these results to measurements on more simple, faster Roman-like image simulations. In both cases, we neglect the impact of blending of objects. We find that in the simplified simulations, Metacalibration can calibrate shapes to be within $m=(-0.01pm 0.10)$%. When applied to the current most-realistic version of the simulations, the precision is much lower, with estimates of $m=(-1.34pm 0.67)$% for joint multi-band single-epoch measurements and $m=(-1.13pm 0.60)$% for multi-band coadd measurements. These results are all consistent with zero within 1-2$sigma$, indicating we are currently limited by our simulated survey volume. Further work on testing the shear calibration methodology is necessary at higher precision to reach the level of the Roman requirements, in particular in the presence of blending. Current results demonstrate, however, that the Metacalibration method can work on undersampled space-based Roman imaging data at levels comparable to the requirements of current weak lensing surveys. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2203.08845v2

Astro arXiv | all categories
Gravitational Lensing in a Universe with matter and Cosmological Constant

Astro arXiv | all categories

Play Episode Listen Later Sep 11, 2022 0:34


Gravitational Lensing in a Universe with matter and Cosmological Constant by Pedro Bessa et al. on Sunday 11 September We extend the results obtained in cite{Piattella_2016, mcvittie_2015} for gravitational lensing in the McVittie metric by including the effect of the transition from the matter-dominated epoch of the Universe to the $Lambda$-dominated era. We derive a formula that agrees with the previous results for the McVittie metric at lowest order, and compare the lensing angle predictions obtained from the Schwarzschild approximation, the McVittie model and higher order corrections to the McVittie model. In doing this, we test if, beyond the correction from the accelerated expansion of the Universe, there is a need for including the matter content of the Universe in modeling lens systems at the redshifts observerd in lens systems. We investigate if there is a need for a modification of the lens equation from these corrections, and if so, to which order and whether it is measurable. We find that while the effect is of the same order as the one calculated previously, there is no significant contribution to the bending angle, as the 1st order effect is already of order $mathcal{O}(theta_O^4)$ in the observed angle. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.04063v1

Astro arXiv | all categories
The Cosmic Telescope that Lenses the Sunburst Arc, PSZ1 G311 65-18 48: Strong Gravitational Lensing model and Source Plane Analysis

Astro arXiv | all categories

Play Episode Listen Later Sep 8, 2022 0:32


The Cosmic Telescope that Lenses the Sunburst Arc, PSZ1 G311 65-18 48: Strong Gravitational Lensing model and Source Plane Analysis by Keren Sharon et al. on Thursday 08 September We present a strong lensing analysis of the cluster PSZ1 G311.65-18.48, based on Hubble Space Telescope imaging, archival VLT/MUSE spectroscopy, and Chandra X-ray data. This cool-core cluster (z=0.443) lenses the brightest lensed galaxy known, dubbed the "Sunburst Arc" (z=2.3703), a Lyman continuum (LyC) emitting galaxy multiply-imaged 12 times. We identify in this field 14 additional strongly-lensed galaxies to constrain a strong lens model, and report secure spectroscopic redshifts of four. We measure a projected cluster core mass of M(

Astro arXiv | all categories
Fermi-GBM Observation of GRB 090717034: χ^2 Test Confirms Evidence of Gravitational Lensing by a Supermassive Black Hole with Million Solar Mass

Astro arXiv | all categories

Play Episode Listen Later Sep 6, 2022 0:59


Fermi-GBM Observation of GRB 090717034: χ^2 Test Confirms Evidence of Gravitational Lensing by a Supermassive Black Hole with Million Solar Mass by Zeinab Kalantari et al. on Tuesday 06 September Gravitational lensing of gamma-ray bursts (GRBs) can provide an opportunity to probe the massive compact objects in the universe at different redshifts. We have discovered two consecutive pulses in the light curve of GRB 090717034, with the same temporal profile and different count rate, separated by a time interval, which is identified as gravitationally lensed candidate in Fermi/GBM GRB catalogue citep{Kalantari}. Here, we use the $chi^2$ method to investigate the similarity of the temporal profile variability of the two pulses as a gravitationally lensed candidate GRB. We find the magnification factor and the time delay between two pulses to correspond to minimising the $chi^2$ function. Then, we perform a Monte Carlo simulation on a sample of mock lensed GRBs and compare the $chi^2$ of the lensed GRB candidate with the simulation, which confirms this candidate with $1sigma$ confidence level. Assuming that GRB 090717034 is lensed by a point-like object, the redshifted lens mass is about $M_L(1+z)=(4.220pm 6.615) times 10^6 M_{odot}$. The lens of this GRB is a candidate for a super-massive black hole along the line of sight to the GRB. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2205.05278v2

Universe Unplugged
Sir Isaac Newton gets schooled on finding exoplanets NEWTON'S GHOST (part 10)

Universe Unplugged

Play Episode Listen Later Mar 29, 2022 3:33


The ghost of Sir Isaac Newton is haunting his great great great grand-niece, Dr. Ivonne! In this sitcom spoof, Newton is trying to catch up on all the science he missed over the past several hundred years, and is particularly curious about the discovery of planets orbiting other stars . Ivonne explains several common techniques of exoplanet discovery including the Radial Velocity technique (detecting a "wobble" in a star), Transit Photometry (measuring tiny dips in a star's brightness as a planet passes), and Gravitational Lensing (a warping of a distant star's light by a foreground planet's gravity field). He even learns that there are planets that don't orbit stars, but rather exist floating in the dark spaces between stars!

Science We Speak
48 | Albert Einstein: The Genius of the Millennium

Science We Speak

Play Episode Listen Later Feb 13, 2022 15:37


Albert Einstein is one of the geniuses of the Millenium for devising his theory of relativity, which revolutionized our understanding of space, time, gravity, and the universe. Keywords: Einstein, Theory of Relativity, EPR Paradox, General Relativity, Special Relativity, Gravitational Lensing, Einstein-Rosen Bridges, Photoelectric Effect.SUPPORT: **Patreon: https://www.patreon.com/ScienceWeSpeakSOCIAL MEDIA: *Instagram: https://www.instagram.com/sciencewespeak/*Facebook: https://www.facebook.com/ScienceWeSpeak*Telegram: https://t.me/sciencewespeak

ASTROPHYSICAST
REWIND: 2021 and Gravitational Lensing

ASTROPHYSICAST

Play Episode Listen Later Jan 2, 2022 7:02


2021 REWIND of the highlights from the field of astronomy. Gravitational lensing: When light passes one of these objects, such as a cluster of galaxies, its path is changed slightly. This effect, called gravitational lensing, is only visible in rare cases and only the best telescopes can observe the related phenomena. Smaller objects, like individual stars, can also act as gravitational lenses when they pass in front of more distant stars.

The Astrophysics Academy: Just A Minute

Learn about gravitational lensing, why it happens, its usage, and its types, all in just 90 seconds!

Astronomy Minute
What is Gravitational Lensing?

Astronomy Minute

Play Episode Listen Later Aug 13, 2020 1:33


A brief description of what a gravitational lens is and how it works.

Fermilab Today Result of the Week
Data from antipodal places: First use of CMB polarization to detect gravitational lensing from galaxy clusters

Fermilab Today Result of the Week

Play Episode Listen Later Mar 6, 2020 9:52


In a study published in Physical Review Letters, Fermilab and University of Chicago scientist Brad Benson and colleagues use the polarization, or orientation, of the cosmic microwave background to calculate the masses of enormous galaxy clusters using a new mathematical estimator. This is the first time that scientists have measured these masses using the polarization of the CMB[...]

Best Of Drum & Bass This Week
Best of Drum & Bass This Week - 7-13-19

Best Of Drum & Bass This Week

Play Episode Listen Later Jul 15, 2019 5:11


Best tunes released and forthcoming in the world of drum & bass. All tunes spun in the mix on Drum & Bass with DJ Pfeif.   ======================== Artist, Song, Label ======================== 1 Voltage, Big Guns, Low Down Deep Recordings 2 Samurai Breaks, No Need, The Dreamers Recordings 3 Mefjus, Bowsar & Kaiza, Gravitational Lensing, Close 2 Death 4 Neonlight, The Frozen Tape, Diascope 5 Samurai Breaks, Party Starter, The Dreamers Recordings 6 Samurai Breaks, Pump Up The Volume, The Dreamers Recordings 7 Neonlight & Hedj, System Error, Diascope 8 Warp Fa2e, Break, Close 2 Death 9 Exile & Mark XTC, Take Me Away (Come Hard Mix), Serial Killaz 10 L Plus, Raw Power, Technique Recordings 11 Agro feat. Killa P, Ruff Ride, Sub-liminal Recordings 12 Maztek, Motherboard Burning, Close 2 Death 13 Samurai Breaks, Wurkdat, The Dreamers Recordings 14 DJ Ransome and SynthForce, Glacier, Celsius Recordings ========================

Curiosity Daily
What to Tell Friends During a Crisis, the Deep Carbon Observatory, and Gravitational Lensing

Curiosity Daily

Play Episode Listen Later Jan 16, 2019 7:23


Learn about how the Deep Carbon Observatory is transforming the way we understand life deep inside the Earth; how gravitational lensing can make gravity act like a magnifying glass to help astronomers see further away; and what to say to a friend who’s dealing with a crisis. In this podcast, Cody Gough and Ashley Hamer discuss the following stories from Curiosity.com to help you get smarter and learn something new in just a few minutes: A New Discovery Points to a Surprising Amount of Life Deep Inside the Earth — https://curiosity.im/2suKkcG Gravitational Lensing Is a Magnifying Glass Made by Gravity — https://curiosity.im/2s6S6JS There's No Perfect Thing to Say In a Crisis — https://curiosity.im/2sf3Nyd If you love our show and you're interested in hearing full-length interviews, then please consider supporting us on Patreon. You'll get exclusive episodes and access to our archives as soon as you become a Patron! https://www.patreon.com/curiositydotcom Download the FREE 5-star Curiosity app for Android and iOS at https://curiosity.im/podcast-app. And Amazon smart speaker users: you can listen to our podcast as part of your Amazon Alexa Flash Briefing — just click “enable” here: https://curiosity.im/podcast-flash-briefing.

StarTalk All-Stars
Time and the Universe, with Charles Liu

StarTalk All-Stars

Play Episode Listen Later Dec 18, 2018 47:44


Can time die? Can we find the origin point of the Big Bang? Astrophysicist and host Charles Liu and comic co-host Chuck Nice answer fan-submitted Cosmic Queries and sing Super Silly Space Songs as we explore time, the universe, and more.NOTE: StarTalk All-Access subscribers can watch or listen to this entire episode commercial-free here: https://www.startalkradio.net/all-access/time-and-the-universe-with-charles-liu/Photo Credit: StarTalk Radio.

A Journey Through Time and Stuff
Pathetic Losers and Gravitational Lensing w Paul Anderson

A Journey Through Time and Stuff

Play Episode Listen Later Dec 11, 2018 201:57


This episode, we had the pleasure of having the amazing Paul Anderson on the podcast. Hes a multi-instrumentalist, bassist for Vespera, and luthier. we discussed a wide range of topics, including Star Wars, physics, atheism, and losers.  Such a good podcast. We also listened to Fleetwood Mac's, Rumours, on vinyl. 

PhDrinking
Cluster of Galaxy Hops

PhDrinking

Play Episode Listen Later Jul 23, 2018 34:01


Fellow ComSciCon- Chicago attendee Gourav Khullar joined me to chat about galaxy clusters. He explained how he models galaxies, infrared telescopes, and gravitational lensing. Suggested Reading: What is a galaxy cluster? http://chandra.harvard.edu/learn_galaxyCluster.html How galaxy clusters tell us a story about the universe: https://astrobites.org/2016/03/17/galaxy-clusters-cosmology-and-beethovens-no-6/ Spectroscopy of Galaxy Clusters: https://www.sdss.org/dr14/algorithms/ancillary/boss/massiveclusters/ Gravitational Lensing employed in Galaxy Clusters (super specific): https://arxiv.org/abs/1303.3274 Follow me: PhDrinking@gmail.com, @PhDrinking, @SadieWit, www.facebook.com/PhDrinking/ Follow Gourav Khullar: @isskywalker, gkhullar@uchicago.edu, http://astro.uchicago.edu/people/gourav-khullar.php Thanks to www.bensound.com/ for the intro/outro Thanks to @TylerDamme for audio editing

5 Minutes With An Astronomer
S01E26: Gravitational Lensing

5 Minutes With An Astronomer

Play Episode Listen Later Jul 3, 2018 6:55


This episode’s question is: we understand that gravitational lensing is one of the predictions of Einstein’s theory of general relativity but what is it?   If you have feedback or a topic suggestion you can email us.

Dr Erin Explains The Universe Podcast
Gravitational Lensing in Star Trek: Discovery

Dr Erin Explains The Universe Podcast

Play Episode Listen Later May 27, 2018 10:26


In this episode, we'll discuss the method they develop in Episode 9 (mid-season finale) of Star Trek: Discovery. Gravitational Lensing and Triangulation...explained! Spoilers, and please accept my apologies for the lighting in this one.

Syzygy
Episode 01: Planets, in a Galaxy Far, Far Away

Syzygy

Play Episode Listen Later Apr 5, 2018 33:41


Find us on Twitter: @syzygypodOr just visit us at home: syzygy.fmEmily is an astronomer at the University of York: www.york.ac.uk/physics/people/brunsden/Chris can be found online: kipstewart.comSome of the things we talk about in this episode:Geocentric models of the universe: en.wikipedia.org/wiki/Geocentric_modelRetrograde motion of planets & heliocentric models: earthobservatory.nasa.gov/Features/OrbitsHistory/Poor Pluto: www.universetoday.com/13573/why-pluto-is-no-longer-a-planet/First exoplanet confirmed 1995: exoplanets.nasa.gov/resources/2084/The transit method: www.planetary.org/explore/space-topics/exoplanets/transit-photometry.htmlKepler mission: kepler.nasa.govExoplanets we know of: exoplanets.nasa.govOur location in the Milky Way: www.universetoday.com/65601/where-is-earth-in-the-milky-way/Douglas Adams’ Hitchhikers opening line: www.goodreads.com/quotes/54481-far-out-in-the-uncharted-backwaters-of-the-unfashionable-endExtragalactic planets paper: iopscience.iop.org/article/10.3847/2041-8213/aaa5fbExtragalactic planets news story: www.sciencealert.com/planets-found-in-another-galaxy-quasar-gravitational-microlensingQuasars: www.spacetelescope.org/science/black_holes/Gravitational Lensing: en.wikipedia.org/wiki/Gravitational_lensEinstein and the solar eclipse: www.forbes.com/sites/startswithabang/2017/07/04/how-a-solar-eclipse-first-proved-einstein-right/#6bda2738766aFunhouse quasar image: phys.org/news/2018-02-astrophysicists-planets-extragalactic-galaxies-microlensing.htmlRogue planets: en.wikipedia.org/wiki/Rogue_planetPlanet HIP13044b: www.space.com/9556-alien-planet-galaxy-discovered.htmlGalactic Cannibalism: www.universetoday.com/89086/galactic-cannibalism/Exoplanet in Andromeda: www.newscientist.com/article/dn17287-first-extragalactic-exoplanet-may-have-been-found/Exoplanet microlensing a quasar: en.wikipedia.org/wiki/Extragalactic_planet#Twin_Quasar-related_planet

HyperStella
HyperStella S01E10 - Dark Matter, Antimatter & Quasars

HyperStella

Play Episode Listen Later Dec 20, 2017 106:41


Dark Matter , Antimatter , Quasars , Gravitational Lensing , Dark Matter Candidates & Experiments , Particle Physics Extended & More.. Be Hypersteller : www.facebook.com/groups/hyperstellacommunity/ WEB : http://hyperstella.com/ Facebook : www.facebook.com/Hyperstella/ Listen to all Sri Lankan Podcasts via : http://podcasts.lk/ Follow Hash: Faebook: https://www.facebook.com/HashCyber Instagram: https://www.instagram.com/HashCyber Twitter : https://twitter.com/HashCyber Youtube : https://www.youtube.com/hashtalk Follow Shavindu: https://www.facebook.com/shavindu.avishka.7 Follow Gayan : https://www.facebook.com/gayan.desilva.940 Follow Thilanka (Sci ): https://www.facebook.com/UTW97 Follow Amila: https://www.facebook.com/Ezio.D.rulzg © Copyright Square Park Studios --- Send in a voice message: https://anchor.fm/hyperstella/message

Cosmic Vertigo - ABC RN
008 | The invisible wind

Cosmic Vertigo - ABC RN

Play Episode Listen Later Apr 20, 2017 27:09


Dark Matter flies through solid walls like a ghost. Humans have buried super-sensitive crystals to try and detect it - and our Universe doesn’t make any sense without it.

Spark Science
Finding Our Way in the Dark

Spark Science

Play Episode Listen Later Mar 27, 2016 48:17


In this episode we talk about Dark Matter, Gravity Waves, Gravitational Lensing and other Astronomy with WWU astrophysicist Dr. Kenneth Rines.     Dr. Rines succeeded in teaching the guest host, Dr. Regina’s brother and local actor, Ruben Chen science (Regina could not).  We had a great time learning about things in the universe that still confuses scientists today.   Enjoy our journey through the mysterious dark of space. Image credit: NASA, ESA, D. Coe (NASA Jet Propulsion Laboratory/California Institute of Technology, and Space Telescope Science Institute), N. Benitez (Institute of Astrophysics of Andalusia, Spain), T. Broadhurst (University of the Basque Country, Spain), and H. Ford (Johns Hopkins University)

Theoretical Physics - From Outer Space to Plasma
Gravitational lensing: one of the sharpest tools in an astronomer's toolbox

Theoretical Physics - From Outer Space to Plasma

Play Episode Listen Later Sep 24, 2015 46:31


Members of the Rudolf Peierls Centre for Theoretical Physics hosted the eighth Saturday Morning of Theoretical Physics on 19 September 2015. Talk 3 by Professor James Binney.

Realspace
Realspace 1: Eric Huff on Gravitational Lensing

Realspace

Play Episode Listen Later Jun 18, 2015 40:24


This week I chat with Eric Huff of The Ohio State University’s Center for Cosmology and Astro-Particle Physics about gravitational lensing, galaxy surveys, and…mermaids. Special thanks to The Ohio State University’s Center for Cosmology and Astro-Particle Physics for hosting this recording session.  You can find more information at realspacepodcast.com or by following me on Facebook or Twitter! Theme song "Live Long and Podcast" by Nick Bain, Into The Machine Recordings (http://intothemachine.bandcamp.com) 2015, all rights reserved.  

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 05/05
Investigating galaxies in and behind Galaxy Clusters using Strong Gravitational Lensing

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 05/05

Play Episode Listen Later Feb 24, 2015


Gravitational Lensing is a unique technique to investigate the dark matter distribution of structures in the Universe, from galaxies, through galaxy groups, clusters, up to the large-scale structure. It allows us to map the total projected mass density of structures acting as lenses, and thus to shed light on the distribution and properties of the otherwise-invisible dark matter. Clusters of galaxies are the largest virialized structures in the universe. Gravitational lensing analysis allows us to study their mass distribution in great detail. Weak lensing probes the mass distribution in the outskirts of clusters based on a statistical analysis of the shape distortion observed in hundreds of galaxies behind the cluster. Strong lensing, instead, allows us to reconstruct high resolution mass and magnification maps of the central region of the cluster. In addition, thanks to the lensing magnification of background sources, galaxy clusters act as "Gravitational Telescopes" and can be used to investigate the galaxy population of the early Universe at z>5. In the first part of my Thesis I use the CLASH and Frontier Fields cluster RXC J2248 to investigate sources at z~6. At such and higher redshift galaxies appear as optical dropouts, since the light they emit is redshifted to NIR wavelengths and no flux is observed in the UV and optical filters. I discovered a z~6 lensed galaxy in the core of RXC J2248 which appears as a quintuple lensed optical dropout in the 16 HST filters of the CLASH survey. I perform a detailed photometric analysis of these dropouts to verify that they present the same photometric properties and are actually multiple images of the same source. In addition, by performing the strong lensing analysis of the cluster core I verify that the lensing model supports the quintuple and z~6 nature of this system. In the second part of my Thesis I use strong gravitational analysis of the CLASH cluster A383 to probe the details of the mass distribution of galaxies in the cluster core. Well known luminosity scaling relations allow us to relate the physical properties as stellar velocity dispersion and size of the elliptical galaxies to their observed luminosity. However in clusters, galaxies suffer tidal stripping due to the interaction with other cluster members and the cluster dark matter halo. The goal of this work is to measure the galaxy halo sizes in a cluster core to quantify how much mass was stripped relative to field galaxies. Here I present a new approach to strong lensing analysis of clusters, in which I use measurements of cluster members' velocity dispersions as additional constraints in the lens modeling. I apply this analysis to Abell 383 to separate the galaxy mass content from the smooth dark matter mass component and investigate how the dark matter halo size scales with the galaxy luminosity in the cluster core. In addition I perform the surface brightness reconstruction of the southern giant arcs to improve constraints on close by individual galaxies and study possible deviations from the global scaling law measured for the cluster.

Universe Today Podcast
Episode 152: 151 - What Is Gravitational Lensing

Universe Today Podcast

Play Episode Listen Later Feb 18, 2015


Support Universe Today Podcast

Universe Today Podcast
Episode 152: 151 - What Is Gravitational Lensing

Universe Today Podcast

Play Episode Listen Later Feb 18, 2015 4:02


Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 04/05
Gravitational lensing studies of galaxy cluster halos

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 04/05

Play Episode Listen Later Apr 11, 2014


Fri, 11 Apr 2014 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/16901/ https://edoc.ub.uni-muenchen.de/16901/1/Rau_Stefan.pdf Rau, Stefan ddc:530, ddc:500, Fakultät für Physik

Innovation Now
Charting the Invisible Universe

Innovation Now

Play Episode Listen Later Oct 15, 2013 1:30


NASA is collaborating with the European Space Agency on a space telescope designed to see and measure dark matter and dark energy

Innovation Now
Euclid

Innovation Now

Play Episode Listen Later Aug 21, 2013 1:30


NASA's is collaborating with the European Space Agency on a space telescope designed to see and measure dark matter and dark energy.

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 04/05
Dark matter distributions in early-type galaxies from strong gravitational lensing

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 04/05

Play Episode Listen Later Apr 16, 2013


Tue, 16 Apr 2013 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/15769/ https://edoc.ub.uni-muenchen.de/15769/1/Eichner_Thomas.pdf Eichner, Thomas ddc:530, ddc:500, Faku

60-Second Space
Galaxy Might Be Most Distant Seen Object

60-Second Space

Play Episode Listen Later Nov 20, 2012 1:15


Thanks to gravitational lensing by a cluster of galaxies, the light emitted by a small galaxy 13.3 billion years ago has reached Earth. John Matson reports

Innovation Now
Dark Matter is Coming to Light

Innovation Now

Play Episode Listen Later Aug 21, 2012 1:30


80 percent of your universe has been in hiding... but new evidence sheds some light on it.

60-Second Space
Dark Matter Bridges Galaxy Clusters

60-Second Space

Play Episode Listen Later Jul 9, 2012 1:15


Gravitational lensing shows that two galaxy clusters are connected by a filament of dark matter. John Matson reports

Naked Astronomy, from the Naked Scientists
Meeting MIRI and Detecting Dark Matter

Naked Astronomy, from the Naked Scientists

Play Episode Listen Later Jan 25, 2012 57:35


Can a mid-infra red view reveal the universe's secrets? In this month's Naked Astronomy, we meet MIRI, the Mid Infra Red Instrument set to launch on the James Webb Space Telescope. It should give us a glimpse of the very first galaxies and examine the clouds of hydrogen gas spread throughout the universe. We'll also find out how distorted galaxies can shed light on the distribution of dark matter, discover El Gordo - a newly discovered galaxy cluster. Like this podcast? Please help us by supporting the Naked Scientists

Naked Astronomy, from the Naked Scientists
Meeting MIRI and Detecting Dark Matter

Naked Astronomy, from the Naked Scientists

Play Episode Listen Later Jan 24, 2012 57:35


Can a mid-infra red view reveal the universe's secrets? In this month's Naked Astronomy, we meet MIRI, the Mid Infra Red Instrument set to launch on the James Webb Space Telescope. It should give us a glimpse of the very first galaxies and examine the clouds of hydrogen gas spread throughout the universe. We'll also find out how distorted galaxies can shed light on the distribution of dark matter, discover El Gordo - a newly discovered galaxy cluster. Like this podcast? Please help us by supporting the Naked Scientists

Naked Astronomy, from the Naked Scientists
Making Steam Inside Stars

Naked Astronomy, from the Naked Scientists

Play Episode Listen Later Sep 24, 2010 54:42


How do you make steam inside a star? We explore the science of solar chemistry to find out how water molecules are created inside the envelope of red giants and We get an delegates-eye-view of the European Planetary Science Congress in Rome. In the news we discover a new way to find asteroids, explain the dust clouds surrounding binary stars and find out how the fine structure constant seems to vary over both space and time. Plus, we take on your space science questions on diluted light, Horava Gravity and building black holes! Like this podcast? Please help us by supporting the Naked Scientists

Naked Astronomy, from the Naked Scientists
Making Steam Inside Stars

Naked Astronomy, from the Naked Scientists

Play Episode Listen Later Sep 24, 2010 54:42


How do you make steam inside a star? We explore the science of solar chemistry to find out how water molecules are created inside the envelope of red giants and We get an delegates-eye-view of the European Planetary Science Congress in Rome. In the news we discover a new way to find asteroids, explain the dust clouds surrounding binary stars and find out how the fine structure constant seems to vary over both space and time. Plus, we take on your space science questions on diluted light, Horava Gravity and building black holes! Like this podcast? Please help us by supporting the Naked Scientists

Lectures and Presentations
Gravitational Lensing: Einstein's Unfinished Symphony (Free Astronomy Public Lectures)

Lectures and Presentations

Play Episode Listen Later Sep 16, 2010 58:05


Presented by Professor Richard Ellis on 7th September 2010.In 1919, Arthur Eddington demonstrated Einsteins's prediction that the Sun's gravity deflects the path of light rays. This phenomonon, termed 'gravitational lensing' is now one of the most powerful tools of the modern astronomer. Professor Ellis reviews the history and progress in charting how dark matter is distributed and how easily galaxies can be located using gravitational lensing.

Free Astronomy Public Lectures
Gravitational Lensing: Einstein's Unfinished Symphony (Free Astronomy Public Lectures)

Free Astronomy Public Lectures

Play Episode Listen Later Sep 16, 2010 58:05


Presented by Professor Richard Ellis on 7th September 2010.In 1919, Arthur Eddington demonstrated Einsteins's prediction that the Sun's gravity deflects the path of light rays. This phenomonon, termed 'gravitational lensing' is now one of the most powerful tools of the modern astronomer. Professor Ellis reviews the history and progress in charting how dark matter is distributed and how easily galaxies can be located using gravitational lensing.

Royal Society Publishing
Professor Richard Ellis

Royal Society Publishing

Play Episode Listen Later Jan 20, 2010 10:39


Wendy Barnaby talks to Richard Ellis about his article on Gravitational Lensing.

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 02/05
Gravitational Lensing in Galaxy Cluster Abell 1689

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 02/05

Play Episode Listen Later Apr 16, 2007


Abell 1689 is a massive galaxy cluster that has an impressive number of gravitationally lensed background galaxies. In this thesis more than 30 multiple image systems identified in A1689 are used to derive an accurate mass profile for the cluster. It is also shown how strong lensing in cluster can be used to constrain the sizes of the dark matter haloes of cluster galaxies and to place upper limits on the amount of dark substructure in clusters.