Mastodawn

RumbleArray Jul 3, 2023

Scientists say quasars demonstrate the early universe's "time dilation," when time then passed only about a fifth as quickly as it does today. https://www.nature.com/articles/s41550-023-02029-2

Detection of the cosmological time dilation of high-redshift quasars - Nature Astronomy

A Bayesian-based analysis of 190 cosmologically distant quasars, photometrically observed over two decades, has revealed the long-expected presence of cosmic time dilation owing to the expansion of space imprinted on their variability.

Nature

Steve Herman Jul 3, 2023

Otherwise known as Mondays among office workers.

aardvark Jul 3, 2023

@w7voa Sounds like you've got a case of the Mondays!

Jan Adriaenssens Jul 3, 2023

Joe Heafner Jul 3, 2023

@w7voa Not if you’re retired. 😏

GlenG🌻 - Support Ukraine Jul 3, 2023

@w7voa 😂 🤣 😂 🤣

Aviva Gary Jul 3, 2023

@w7voa cool and also hilarious

Honey Jul 3, 2023

@w7voa Not sure the title reflects the contents. Time didn’t pass any differently then if you happened to live near one of these quasars (although nothing did!). The paper refers to *apparent* time dilation i.e. from our perspective, meaning that we see time passing more slowly there from here, in the form of the variability of these quasars appearing longer to us than it would appear locally. This is expected, but not seen before quasars.

David Stucky Jul 3, 2023

@honey @w7voa So the waves are being stretched thin like photons scraped too much space.

Honey Jul 3, 2023

@Tarkin2258 @w7voa It’s a long time since I studied this, but the universe is much bigger today than it was when this light set out from these quasars. So space itself has been spread out across the intervening distance/time. I am however quite sure that there are many current theoretical physicists on Mastodon how could explain this better! I’m merely reading the abstract. If these are general relativistic effects, I’m going to run away very quickly from trying to even attempting to explain it.

David Stucky Jul 3, 2023

@honey @w7voa It's all good.

I prefer my more concise response above. But, I can stretch it out a bit with more nonsense.

I am going to go with given time, a known expansion of space, the rate of photon production by a quasar is what is, and space expands, not mater, that the number of photons does not change. So they either have to separate (act like a particle) or stretch (act like wave) to file the gap left by expanse. If you stretch a wave, it takes longer to experience. If you separate particles they will strobe, blink or twinkle to a beat. And yes, I am just looking at it from a practical observation point of view; how would I perceive it. Not a science thing.

Honey Jul 3, 2023

@Tarkin2258 @[email protected] That would certainly be a metaphorical way of explaining redshift, i.e. the wavelength of the light shifting into the red side of the spectrum the further away the quasar is. This observation measures a change in the periodicity of light from quasars (thought to be like cosmic clocks). But yes, I think maybe both observations are a result of time dilation, the first being observed in the 1930s, the second only confirmed now for quasars.

Graham Sutherland / Polynomial Jul 3, 2023

@w7voa "by assessing various hypotheses through Bayesian analysis" this does not bode well

Graham Sutherland / Polynomial Jul 3, 2023

@w7voa also, time dilation is dependent on the frame of reference. time didn't actually pass more slowly, it's our observation of it that's dilated.

Patriotic Cats Jul 3, 2023

@w7voa so it’s not just me

Uncle Jamie Jul 3, 2023

@w7voa So, what are the units of measure for the speed of time’s passage? s/s ? Whatever they are would be the same units in which to measure the speed of a time machine.

happyborg Jul 3, 2023

@w7voa I'm struggling to understand time dilation.

I understand that expansion results in red shift as a function of distance in spacetime by setting the wavelength of starlight.

I'm not sure how expansion speeds up time though. 🤔

phine Jul 3, 2023

@w7voa Not directly to the post but considering the accelerating expansion of the universe.. is there no reason it is not just a colossal diffusion across a gradient... zero space and stuff thrown in explosively it accelerates until diffusion is complete.

Jonathan Hendry Jul 3, 2023

When was that, 1978?