Lazytown Classroom (5)

[boredjedi]

No, it doesn't at all. It's a brand new paper with a new theory that is neither LCDM nor MOND. Read the article. It's about time passing at different speeds in empty areas than in matter dense areas. What was perceived as acceleration is actually just more time passing, and things moving farther apart over that time, in low gravity areas like voids because time runs faster there.

Omg I got blue screened in the middle of typing this It. doesn't do it as much with the 24H2 update but it still happens every now and again.

I had read it and came away with Timescape being just an offshoot of MOND. Neither needs Dark Matter and Dark Energy.

From the article: "It takes into account that gravity slows time, so an ideal clock in empty space ticks faster than inside a galaxy."

That's how I always thought of it. And what I took away from that video. It's all pretty much covered in that video.
Matter, gravity, time and speed. High gravity greatly slows time. Low gravity does slow time but not as much.
No gravity time would pass unaffected. Meaning the baseline for time. Even in these voids, there is effects of gravity. Either from the local
galaxies residing in the void and gravitational influences from matter outside the void. All of it though still depends on our understanding
of gravity.

[boredjedi]

I bet a lot of the James Bond stuff today goes on at router factories. If you can get access to routers in the factory/the manufacturing process, you can put hardware (not just firmware) backdoors on the boards. I think China was caught doing that a year or two ago.

That's a definite. Started after 2009 with CPUs. That Intel Management Engine issues. AMD joined in too
AMD Secure Technology (formally called Platform Security Processor) after 2013 .
But I'm sure there's stuff nobody has discovered yet. I remember gloating about my
AMD chip from 2009 was clean of that public dubious backdoor stuff. Now
with the new AMD CPU I'm snooped on no doubt. Besides the Windows snooping.

In the immortal words of Weird Al "Be aware: There's always someone that's watching you."

Wait thought there was a spy Steph emoji image.

[chuft]

Isn't this just how the formule works.

speed = m/s(t)

If you want to explain why a distance is longer (in empty space), make the time smaller (faster time) and the speed increases.
Or inside a galaxy the distance is shorter, so make the time larger (slower time) and the speed decreases.

So time is the variable. But why? Only because of gravity?

Yes. Time moves slower in a gravitational field. Even on Earth this is an engineering problem because satellites in orbit - like GPS satellites - have to keep precise time and be in sync with the ground, but time passes more slowly on Earth's surface than it does in orbit, because the surface is deeper in the gravity well. Adjustments have to constantly be made because time is passing faster in orbit and the satellite clocks run faster than clocks on Earth.

Acceleration is similar. Say you have a guy on a space station and a guy in a rocket ship. The ship flies away then later flies back. One of the two guys will be older when the ship gets back. Now in Einsteinian physics we have relativity, you can view the ship as standing still and the station moving away, or you can view the station standing still and the ship moving away. Both are valid and it just depends on the observer's point of view.

But the fact is one guy is younger after all this. And it will be the guy on the rocket. The reason is because he is the one who really moved away. How can you tell? He experienced acceleration. As things speed up they become more massive, gravity increases and time slows down. He aged less during the trip because he accelerated away, then accelerated in the other direction (decelerated) to stop, then accelerated back towards the station, then accelerated away (to slow down) in other direction to stop at the station.

He felt the acceleration (like you do when in a car and you speed up and are pulled back into the seat) and instruments would measure it as force just like gravity. Inside a spaceship with no windows you can't tell whether a force you are feeling is gravity or acceleration. There is no difference.

This slowing down of time due to acceleration and increase in mass is why you will sometimes read about the idea of someone traveling close to the speed of light on a long trip and coming home only to find hundreds of years have passed on Earth but only a few days or months for the person on the ship.

But yes the paper is saying that due to the increased mass in areas of the universe that have stars, time runs slower there, while in the great voids, time moves much faster. Therefore the expansion has more time to go on and things look farther away than they should from the point of view of the mass rich area. For someone on Earth 8 months might go by while 12 months has gone by in the void. This gives an extra four months in the voids during which moving objects move further. To us it looks like they are moving really fast, but they aren't, they just get more time to move in.

[chuft]

Omg I got blue screened in the middle of typing this It.

Your computer knew it was wrong.

I had read it and came away with Timescape being just an offshoot of MOND. Neither needs Dark Matter and Dark Energy.

No, MOND changes the laws of gravity to account for observed phenomena on the edges of galaxies being different than expected. This paper isn't requiring a change to the laws. It is saying the time difference explains why stuff in matter poor areas seems to be moving faster than in matter rich areas.

From the article: "It takes into account that gravity slows time, so an ideal clock in empty space ticks faster than inside a galaxy."

That's how I always thought of it. And what I took away from that video. It's all pretty much covered in that video.

I can't tell you how you always thought of it, but I watched the entire video and it definitely does not say anything about time explaining the observations. Which is not surprising because this is a major new paper by a group of astrophysicists, and that is a month old video by who knows who. This is a major challenge to LCDM and the idea of dark energy, saying the current laws of physics explain the observed phenomena without requiring the "law of gravity change" of MOND.

Matter, gravity, time and speed. High gravity greatly slows time. Low gravity does slow time but not as much.
No gravity time would pass unaffected. Meaning the baseline for time. Even in these voids, there is effects of gravity. Either from the local
galaxies residing in the void and gravitational influences from matter outside the void. All of it though still depends on our understanding
of gravity.

The video does not say that the apparent acceleration of the universe expansion is actually just due to time passing faster in some regions than others due to differences in mass. That is what makes the paper so important.

[boredjedi]

The video does not say that the apparent acceleration of the universe expansion is actually just due to time passing faster in some regions than others due to differences in mass. That is what makes the paper so important.

Yeah I got that. Maybe I was reading more into that video than there was or
there was another video I watched that involved time, mass the usual.
Not the same as that paper but on the same theme.

When I read that paper, it sounded all so familiar. Local differences in time and gravity/mass etc..
Even the Earth doesn't have uniform gravity due to clumpy matter which would affect time imperceivable to us
but is measurable with the equipment they have nowadays. Even the tippy top of the atmosphere
at the space boundary is not uniform. I can imaging then that the boundary of the universe is not uniform either.
Clumpy. Assuming there is a boundary. Time will tell which model is right LCDM, MOND and now
Timescape (assuming it holds up to further independent observations). The battle continues.

Bottom line to all this is that we all have to keep adjusting our clocks