Lunch time doubly so
this post was submitted on 04 Jun 2024
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just science related topics. please contribute
note: clickbait sources/headlines aren't liked generally. I've posted crap sources and later deleted or edit to improve after complaints. whoops, sry
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Don’t panic, and always remember to bring a towel
“I never could get the hang of Thursdays.”
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time being purely a consequence of entanglement. It states that the only reason that an object appears to change over time is because it is entangled with a clock.
Wtf. Which clock is this?
One of those cat clocks with the eyes that go back and forth.
Yeah. I read that multiple times and still have no idea what he’s talking about but it’s the most important part of the article
They mean something that can be used to mark change, they mean clock in the purely physics sense... but don't worry, you're probably not dumb, these articles are so horrible at communicating theoretical physics ideas it might as well be abstract, new-age greeting cards.
I also figured that they meant entangled with some system that can mark change, but change is only possible with a concept of time. So I still don't follow.
I think they mean that a quantum system entangled with another quantum system serving as a clock will create the appearance of classical physics including classical notions of time in the system when you observe it from a macro scale?
That way this theory tries to bridge the gap between quantum notions of spacetime and classical notions of space and time?
If that's not what it is then it's beyond me what they're trying to say.
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“Probably not dumb” love the honest appraisal of unknown variables. I’m like the science fan in big hero 6. Not smart enough to do science but smart enough to enjoy it.
This clock concept is still so abstract I don’t know what the “clock” could possibly be or look like
In a very basic sense a "clock" is just a fixed oscillation. In CPUs, for instance, all your data is carried by bursts of electricity that you can think of like Morse code. Bits are delineated by the clock, which is one wire that lights up on a regular interval and does nothing else (the "clock signal"). Every other process uses that clock signal as a reference point to know when one piece of data ends and the next begins. Essentially the time between one clock signal and the next is one "frame" of CPU time and you'll usually have a few million or so of those every second.
So if we think of this in a physics sense instead of a computer science sense, a physics clock could be any particle or particle interaction that happens repeatedly on a regular schedule. It could even happen on an irregular schedule, there's no law saying the clock has to be consistent. I think it's probably on a regular schedule, but for all we know the pico-femto-Planck or whatever the basic unit of time ends up being defined as might have slight variance caused by who knows what. But the important idea to take away is that a "clock" in a fundamental sense is basically just any action that repeats. It could be or look like anything. Maybe time is tied to quantum foam fluctuations, or gravity in a general sense, or specifically the up quark doing something. I have no idea and I think this researcher probably doesn't either.
Perhaps it is just a very dry physics joke
The one in my basement. It's a bit dusty. Should I turn it off?
Hold on, let me find a moment of happiness first.
Noooo!!!!
THE clock
And how did time pass before the invention of the clock?
I wonder if he's talking about a some kind of "clock circuit?"
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thank you, I hoped this would be here.
As is birth. Both sides of the dichotomy are dropped in Buddhism. Focusing on death is letting go with one hand, and clinging with the other.
Summary: time is entangled with a clock and appears static from the outside. Why, the article doesnt explain.
Just as I always suspected
If we break the illusion will it fast forward me out of existence?
Yeah you got to be real careful you don't zero sum yourself, much better to chim if you can
Unexpected truestl
Sweet, sweet release.
I thought it was widely agreed that time was a construct?
It has been a common belief in philosophical circles for centuries, but not among physicists. Both Newton and Einstein thought of time as being one of the fundamental properties of the physical universe.
However, in the past decade or two, some theoretical physicists have now come back around to the idea that space and time could instead be emergent properties of a deeper, underlying reality.
If you really want to go cross-eyed, read up on the holographic principle.
My favorite theory is that time and space are reversed in a black hole which could be at the beginning and the end of the universe.
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In relativity time is a real dimension like space , but of a different type, and your speed in time depends on your speed in space and on your proximity to big masses, like planets. This kind of physics is necessary to keep the satellites synchronised otherwise their clocks go at a different speed from those on earth, so this is all very real and confirmed.
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"What the hell, Jenson?!? This is our firms biggest case in 20 years and you show up two hours late?!?"
"Oh, haven't you heard?"
next up: coordinate systems don't exist
Can't even read it.
We present an implementation of a recently proposed procedure for defining time, based on the description of the evolving system and its clock as noninteracting, entangled systems, according to the Page and Wootters approach. We study how the quantum dynamics transforms into a classical-like behavior when conditions related to macroscopicity are met by the clock alone, or by both the clock and the evolving system. In the description of this emerging behavior finds its place the classical notion of time, as well as that of phase-space and trajectories on it. This allows us to analyze and discuss the relations that must hold between quantities that characterize the system and clock separately, in order for the resulting overall picture to be that of a physical dynamics as we mean it.
"evolving system and its clock as noninteracting, entangled systems"
Interesting. Is this related to https://en.wikipedia.org/wiki/Eternalism_(philosophy_of_time) ? (Block Time)
Bare with me here because I am not an expert. I think what they're getting is the same as how gravity doesn't exist. Vsauce did a great video on that, but the general notion is that because space time is curved, objects traveling in streight lines will appear to be drawn closer to one another. "Gravity" isn't fundamental, warping spacetime is. Nothing changed but our understanding of it, which does matter for some more complicated areas.
I think this is similar. Just like gravity "doesn't exisit", it's just an emergent phenomenon: they're saying so is time. They're saying time isn't fundemental, except that it's an expected phenomenon that would arise from other factors, those factors being proposed to be some entanglement crap I have zero ability to talk about.
And I'm putting some words in their mouth with "time isn't fundemental". What they're really doing is proposing a new definition that better fits observed phenomenon/models.
And still, none of this explains why we still have daylights savings time.
zfs snapshot create universe@0
zfs mount universe
Do I have that right ?
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