Is the flow of time considered work? If not, would the expansion of space be considered work? Is there a difference?
Someone smarter than me will probably have a better answer, but I would say no; as time is relative.
But, I’d also say “work” cannot happen without the flow of time.
TIME
a nonspatial continuum that is measured in terms of events which succeed one another from past through present to future
WORK
activity in which one exerts strength or faculties to do or perform something
I would build upon @Grrr 's comment that work cannot happen without the flow of time.
Time is required for work to exist. But work is not required for time to exist.
ETA: oh, and welcome to the Dope.
The OP (original poster for newbies) is clearly asking about physics so I don’t think a dictionary definition of work is going to cut it. The physical definition is work = force X distance.
Force is mass X acceleration or mass X distance / time 2 so work is mass X distance s / time 2.
So, yeah, no time; no work.
Thank all of you, that clarifies the issue. One more question, does the expansion of space count as work?
Not sure if I’m qualified to answer but I’d say no. The expansion of space does not move things further apart. It creates more space between things so they look like they moved but they didn’t.
But let’s say you had a large mass - like, the size of a planet - attached to a long chain - like, a couple (or would it need to be a couple hundred?) light years long. The chain is at its end wound around a winch. As the expansion of space carries the planet further away, the chain is unspooled, pulling on the winch and turning it.
If you could extract energy from the expansion of space in this way, even theoretically, wouldn’t that mean the expansion of the universe IS work? Or at least, can be converted into work?
Why wouldn’t the “space” along the path of the chain not also expand?
It would, but the individual atoms that make up the chain are bound to each other with enough force all along the chain that they’d stay intact, so the chain should be pulled along with space. Just like how Earth orbits the sun despite the space between them expanding, or how our sun is gravitationally bound to distant stars on the other side of our own galaxy due to being bound to other stars in between. Only more so because atoms are held together by stronger forces than gravity.
My logic is, since work=force*distance, and the distance between objects is growing, than all that is left is the force part. I believe that this would be caused by dark energy, although I could be wrong.
What confuses me is IF the expansion of space is considered work, than should the flow of time also be considered work? I might have a misconception, but if we look at the distance in terms of time, than the parts of the work equation should be filled out. Unless there is no force involved in time progressing, I don’t understand why it wouldn’t be considered work.
If the two planets you have chained together are already moving relative to each other, then you’ll be extracting the energy from their kinetic energy, and they’ll eventually stop relative to each other. If they’re not already moving relative to each other, then they’ll remain not moving relative to each other. It’s not like either of them is “anchored” to space.
If time = zero (actually delta time) you have a division by zero problem, and the answer would be in what happens to distance as time goes to zero. But approaching zero one starts to hit the quantum limits of time and space which I believe are unknowable (as is uncertainty) but also indivisible. If you go further towards zero then quantum limits I guess that breaks spacetime, thus time can not not exist if anything does exist.
I think this is the nub of the question.
If space is expanding, and we assume we have arrived at a steady state where the planets have stopped moving relative to one another, what happens to the chain as space further expands. Especially if the expansion of space is accelerating. Assume intergalactic distances.
From this it hints that it may be possible to have work without time at a quantum level, however it may not be possible to measure it without time or at least all in an instant moment of time.
This sort of makes sense in a weird quantum way as particles can be (and are) in multiple places at the same moment of time. Thus distance is accomplished.
However, we must still consider the paradox in which my being at work causes time to cease to flow.
Space is cooling down as it expands and entropy increases. I am not a physicist, but I do not see this as work, thermodynamically.
It’s like a gas expanding into an empty space. No work happening there
Well, Albert E. did make a similar, important, discovery.