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.
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.
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.
This is the crux of quantum field theory, no? Where Newtonian and Einsteinian physics are all entirely emergent properties of fields that are governed by quantum principles? I’m in the cross-eyed camp so I’m way out my depth.
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.
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"
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.
I would suggest, instead, that "Classical Physics" is created by entanglement:
the non-quantum reality at our scale is just what happens, when everything is entangled, to the point of clogging-up-the-works of quantumness, as it were..
.: you get things like .. as you scale up from quantum-level .. the everything-is-discontinuous/everything-is-turbulence .. turns into, once enough entanglement is happening, "laminar flow" in fluid-dynamics, even-though NOTHING in QM is laminar-flow, so there's simply no basis for "laminar flow" at the lower-level...
I would be careful of confusing "reality" (whatever that is) with our model of reality. Relativity, which treats time as a dimension, is a good model that fits well with most of our observations. It's not perfect, though, and it doesn't fit well with some other observations. That's how we know that it doesn't fully match reality, and why we're looking for a new model.
Paraphrasing the old saying: all models of the universe are wrong, but some are useful.
What effect does the distinction between that and "the best way we have for our minds to think about it" have on it?
Also, unless i remember it wrong, I thought it was relativity that showed the flaws explanation quantum physics' had for time and not the other way round. I mean, I might be but that's my understanding of it right now.
It absolutely does depend on your reference frame. I remember one of my physics 3 test problems was a ship in it's own reference frame was a standard 3 4 5 right triangle. We had to calculate what the observed lengths and angles from a reference frame where it was moving at .96c.