#Interferometry

[materialsscienceandengineering]

A new simple scheme for atom interferometry

Atom interferometers are devices that use the wave characteristics of matter to measure the phase between atomic matter waves to separate paths to make high-precision measurements of elements of physics, such as gravitational and magnetic fields. Atom interferometers have also found their way into industry and are used in geological surveys, mineral exploration, environmental monitoring, and for the development of precision atomic clocks. Atom interferometers usually control matter waves and particularly particle velocity using lasers. Thus, the growth of atom interferometer application has been strongly tied to the development of advanced laser systems, with many current models based on the construction of gratings fashioned from laser beams.

Read more.

[boredphysicsstudent]

Michelson-Morley type interferometry! The ring pattern shown here is a special type of pattern that shows up when a coherent light source (think lasers, not light bulbs) interferes with itself.

I wish I had better photos of the interference patterns.

[truphysics]

Interferometry

Introduction Interferometry is a family of techniques in physics which use the phenomenon of interference to make precise measurements of various quantities. It involves superposing (or “mixing”) waves to extract information about the waves or the media they have interacted with. Basic Principle The basic principle of interferometry involves splitting a wave into two or more parts, allowing…

[spacenutspod]

SpaceTime Series 27 Episode 140 *Revisiting the Milky Way's Black Hole Image A new study questions the accuracy of the first-ever image of Sagittarius A, the supermassive black hole at the centre of the Milky Way. Researchers suggest the image may not accurately represent its appearance, proposing a more elongated accretion disc instead of the ring-like structure previously released by the Event Horizon Telescope. *Methane in Titan's Crust Data from NASA's Cassini spacecraft indicates that Saturn's moon Titan may have a methane-rich crust up to 10 kilometres thick. This insulating layer could explain Titan's shallow impact craters and its methane-rich atmosphere, providing insights into its unique geological and atmospheric dynamics. *Updates on Earth's Ozone Hole NASA reports that the annual ozone hole over Antarctica was smaller this year, ranking as the seventh smallest since recovery efforts began. The ozone layer is on track to fully recover by 2066, thanks to international agreements curbing ozone-depleting chemicals. The Science Report Antarctic ice core samples suggest Earth has already surpassed a 1.5°C global temperature rise due to human-induced climate change. A study links outdoor lighting at night to increased Alzheimer's risk for those under 65. LED lights on surfboards could reduce shark attacks by mimicking natural camouflage. Nord's latest survey reveals continued use of weak passwords, with "123456" and "password" among the most common. www.spacetimewithstuartgary.com www.bitesz.com 🌏 Get Our Exclusive NordVPN deal here ➼ www.bitesz.com/nordvpn. Enjoy incredible discounts and bonuses! Plus, it’s risk-free with Nord’s 30-day money-back guarantee! ✌ Check out our newest sponsor - Old Glory - Iconic Music and Sports Merch and now with official NASA merch. Well worth a look.... Become a supporter of this Podcast for as little as $3 per month and access commercial-free episodes plus bonuses: https://www.spreaker.com/podcast/spacetime-with-stuart-gary--2458531/support 00:00 New study suggests first ever picture of Milky Way's black hole might not be accurate 00:47 New study claims first ever images of Sagittarius A may be inaccurate 03:57 New study suggests Saturn's moon Titan may have an insulating methane crust 09:12 Scientists say Antarctic ozone layer could fully recover by 2066 20:04 New study suggests Earth has already passed 1.5 degrees Celsius warming attributable to climate change 21:24 A new study claims exposure to outdoor lighting at night increases Alzheimer's risk 25:29 Space Time with Stuart Gary is available on numerous podcast platforms

[superpte]

Macrorealism Epic Fail Experimentally Demonstrated By Violation Of LGI!

Quantum Physics is not real in the sense that one expects "real" to mean. That has now been formally experimentally demonstrated by the violation of the Leggett Garg Inequality in interferometry. The consequences are tremendous. E.g. space is more than 3D

Abstract: We now have a formal experimental proof that what is observed is not all what is going on: violation of the LGI, the Leggett-Garg Inequality have been observed with 18 sigmas certainty. This has huge consequences I will draw in another essay.   *** Folksy: You convoked us, master, to criticize “MACROREALISM”, what is that? Tyranosopher: Macrorealism says that the world always is, at…

[dnieperrobot69420]

Interferometry

So I am studying optics right now, and the topic of interferometry keeps coming up!!

Because light can be modelled like a wave using maths, we know through the Double Slit experiment that two point sources can exhibit constructive and destructive interference.

So far, I have learned about the Double Slit interferometer ( the first one), the Michelson interferometer (book says it can be used to measure refractive index of gases) and the Fabry Perot interferometer (wavelength measurement).

I don't know *exactly* how they work, but I got excited when I found out that the Fourier Transform is used to show the frequency domain (spectral resolution) of optical signals much like in EE!!

Once I finish this chapter, its time to learn about Multiple Beam Interference, I looked at the pictures; lots of triangles, trigonometry, and a hodgepodge of algebra!

[ourwitching]

Screenshot of the Zygo white light interferometry microscope software. (Credit: Huygens Optics) Whit...

[pitch-and-moan]

SPIDER God

A biopic about physicist Ian Walmsley. The film completely ignores the contributions of Chris Iaconis.

[mentalisttraceur]

Symbiotic Disorders

We know this idea as a joke: "I'm not healthy, I just have a system of perfectly balanced disorders". But I think this is a useful model to try out, especially for mental stuff. What would happen if at least two disorders can coexist and mask each other?

It could hide or stop dysfunction or the differentiating features so much that the person doesn't fit either diagnosis - but internally there is still all the pain and struggle of the disorder. It's worth remembering that when trying to understand others, and ourselves.

It might help you be more durable, willing, or able in certain roles, in the face of certain pressures and risks - maybe sometimes that's even worth the personal cost?

It would be harder to heal, improve, or even acknowledge problems, because each disorder is now load-bearing. You try to give some advice a fair shake, you work on being healthier, and yet you get worse outcomes which you know your old ways reliably prevent.

[mentalisttraceur-long]

A key thing about abused kids....

Kids are often so far away from knowing what's abusive and what isn't, and from even having a correct interpretative lens about it, that if you naively ask them to describe their home life, odds are extremely high they won't even think to mention a lot of the abusive stuff.

Because it doesn't even stand out to them. And the worst stuff that does stand out? Well that was obviously because they "deserved it" or "brought it upon themselves" or whatever. They might feel shame bringing up any of the stuff they did that the abuse was punishing.

They don't know that their dad doing a thing that physically hurts and leaves them unable to breathe for a while is abusive - they think surely other dads do that too when you make them mad, or worse, and honestly their dad is better because that's not hitting, it never bruises or bloodies or breaks anything and it doesn't even hurt that much.

They don't know that that one time their dad seriously hit them when they were like five is fucked up enough to mention - they think it totally makes sense because they did something that exceptionally raised negative feelings, surely any parent would.

They don't know that the one time they half-performatively ran out of the room because mom hurt herself doing something and expressed angry frustration, and then mom chased after them yelling and hit them, because she interpreted the kid's played up fear whimper sounds as laughter rather than as a meta comment on fearing literally exactly this behavior that mom is now doing... yeah they don't know that's particularly worth commenting on because that event is the only one they still remember but it's memorable precisely because it was an exceptional situation that's the most understandable.

They don't know being made to retrieve and eat food out of the trash that one time is abusive - they think "well I did waste some of that food, and I deprived someone else in the family from eating it who might've enjoyed it" and then don't even think anything of it until they're in their fucking thirties and two years deep into a self-chosen unemployment after they've realized they need something that drastic to work through everything.

And when that's the highlights, they're not even going to think about how every argument happens in the intimidation shadow of getting physically hurt if you make a parent too mad or stand up for yourself too angrily. They're not going to bring up all the yelling and chronic drip of self-esteem-damaging insults about their intelligence and moral character that come out whenever they do something bad or not-actually-bad-but-apparently-adults-think-its-bad or bring home bad grades.

They sure as fuck aren't going to think to mention the kinds of data points that a psychology-versed person will immediately recognize as textbook cause of CPTSD, but which to the kid just seems too subtle of a detail within their normal to even mention, like "oh, and I can never know if the yelling is done - it could randomly resume at any time if one of the parents thinks of another Great Point to make about how I'm bad or am doing bad things to my life or [...] - so sometimes I only fall asleep long after the yelling has stopped because I noticed that the sounds outside my bedroom have distinctly indisputably shifted to my parents talking pleasantly about something amongst themselves, or the lights have gone out".

Point being: if you just naively ask an abused kid to describe their experiences, they're probably not even going to think of a lot of the right stuff to bring up. You gotta really try to creatively apply your more experienced perspective to feel around, think of possibilities, ask questions that would trip over some detail, and most of all you gotta notice relevant mental movements in them and ask yourself what kind of abuse pattern might cause them.

[scienza-magia]

Rilevazione dei messaggi dallo spazio profondo

In due anni rilevati 200 segnali di onde gravitazionali. Ora i rivelatori Virgo, Ligo e Kagra in pausa per 9 settimane per la manutenzione. Negli ultimi due anni, a partire dal maggio 2023, sono stati 200 i segnali di onde gravitazionali catturati complessivamente dal rilevatore europeo Virgo, che si trova in Italia, a Cascina (Pisa), dalla coppia di rivelatori americani Ligo e dall'osservatorio giapponese Kagra. Adesso i quattro interferometri entrano in una pausa programmata di nove settimane per la manutenzione. Nel frattempo Virgo resta aperto ai visitatori, che sono oltre mille al mese. L'osservazione di 200 eventi segna "un record impressionante, se si considera che complessivamente nei precedenti periodi di osservazione i segnali rivelati sono stati 90", rileva in una nota l'Osservatorio Gravitazionale Europeo (Ego) al quale fa capo Virgo. L'incremento si deve alla maggiore sensibilità dei rivelatori, frutto delle innovazioni tecnologiche realizzate negli scorsi anni. I quattro rilevatori torneranno in funzione a pieno ritmo il 7 ottobre, quando il quarto ciclo di osservazioni si concluderà ufficialmente. Inizialmente la pausa era dovuta alla necessità di riparare una valvola di chiusura del rivelatore Ligo che si trova a Livingston (Louisiana) prima della stagione degli uragani, ma è l'occasione per lavorare su tutti i rivelatori della rete.

Ricercatore al lavoro su uno degli specchi del rivelatore Virgo fonte. EGO-Virgo Maurizio Perciballi A Cascina i ricercatori di Virgo stanno approfittando della pausa per sostituire uno degli specchi principali dell'interferometro, all'estremità del braccio ovest. L'operazione di sostituzione in corso è molto delicata e richiederà circa un mese, dice Diego Bersanetti, dell'Istituto Nazionale di Fisica Nucleare di Genova. Per il portavoce di Ego Gianluca Gemme, dell'Infn, "la nuova astronomia gravitazionale sta rivoluzionando il nostro modo di osservare e studiare il cosmo. In soli 10 anni dalla prima rivelazione di un'onda gravitazionale, le nuove informazioni che abbiamo acquisito stanno trasformando le ipotesi degli astronomi sulle popolazioni di buchi neri e alcuni modelli dell'evoluzione stellare". La grande attesa della comunità astronomica per i prossimi mesi è replicare una nuova osservazione multimessaggera, ovvero l’osservazione coordinata e simultaneo di uno stesso evento cosmico utilizzando segnali di natura diversa, come onde gravitazionali, luce, onde radio, raggi gamma. Finora questo è accaduto, con l’osservazione della fusione di due stelle di neutroni. Read the full article

[things-i-said-while-high-in-bed]

What did I do last night?! Did I explain gravimetric interferometry?

[jayther]

How did they actually take this picture? (Very Long Baseline Interferometry) via YouTube https://www.youtube.com/watch?v=Q1bSDnuIPbo

[truphysics]

LIGO (Laser Interferometer Gravitational-Wave Observatory)

Introduction The Laser Interferometer Gravitational-Wave Observatory (LIGO) represents one of the most ambitious and successful projects in experimental physics. It was designed to detect gravitational waves, ripples in the fabric of spacetime caused by violent cosmic events like the collision of black holes or neutron stars. Theoretical Background: Gravitational Waves Gravitational waves,…

[spacenutspod]

This episode is brought to you with the support of NordVPN. For our special Black Friday deal complete with 30 day money back guarantee, visit www.nordvpn.com/spacenuts.  Space Nuts #462 Q&A Edition Join Andrew Dunkley and Professor Fred Watson in another enlightening Q&A episode of Space Nuts, where they tackle intriguing questions from listeners around the globe. From the perplexing nature of dark matter and dark energy to the possibility of interferometry using Space and ground-based telescopes, this episode is packed with cosmic curiosities and insightful discussions. Episode Highlights: - Dark Matter and Dark Energy in the Solar System: Trent from St. John's, Newfoundland, Canada, questions why dark matter and dark energy, which comprise 96% of the universe, are not factored into the movements of our solar system. Fred Watson Watson explains the scale and influence of these mysterious forces. - Interferometry with Space Telescopes: Bo from Victoria wonders if it's theoretically possible to perform interferometry using Space telescopes like Hubble and James Webb, combined with ground-based telescopes. Explore the current limitations and future possibilities of this technology. - The Mystery of Gravitons: Vincent questions the existence of gravitons and their potential to form self-propagating waves. Delve into the intersection of quantum theory and relativity as Fred Watson Watson discusses this theoretical particle. - Biblical Floods and Astronomical Events: Christopher from Bayville, North Carolina, inquires about the possibility of biblical floods being linked to astronomical events. Discover the fascinating connections between historical events and cosmic phenomena. For more Space Nuts, including our continually updating newsfeed and to listen to all our episodes, visit our website at www.spacenutspodcast.com. Follow us on social media at SpaceNutsPod on facebook, X, YouTube, Instagram, and TikTok. We love engaging with our community, so be sure to drop us a message or comment on your favourite platform. For more Space and Astronomy News Podcasts, visit our HQ at www.bitesz.com. Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts/support. Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.

[studiousandrogynousfox-blog]

maybe physics is cool?

i've been struggling with not looking physics anymore. for. a. while. maybe it's because i've been doing both my undergrad and grad part time and i feel like i forget what i've learned faster than i'm learning it? or maybe it's because it's just talking soooo long? but i've also gotten bored of my small research project already, which i started at the beginning of march.

but, today, for the first time in quite a while, i actually thought to myself "physics is cool". so maybe i do still like physics? maybe i'm reaching the end of this marathon and i'm just exhausted? but maybe, once i've had a chance to recover, i'll fall back in love with physics again?