Is the absolute center of a spinning object moving or stationary?

[Halbhh]

Is the absolute center of a spinning object moving or stationary?

I was hoping to find more info online about this than I did. Does anyone know? Is there a better way to frame the question in order to get better search results?

In abstraction you could go down to a point, infinitesimal, and then at that mathematical limit, you'd have to decide whether it is moving, or not, a fun question. heh heh. (Let me put aside the reference frame: 'moving' relative to what, since that's not really the interesting question.) But in quantum mechanics things near to that scale, so small, are quantitated, and there is a fundamental unit of spin even.

So, matter that has spin has units of spin it must assume some quantized amount of.

Really though, normal matter (the kind we are familiar with) on the atomic scale has some basic level of motion we call 'temperature', such as in vibration, etc. unless you could cool it to absolute zero (again, not something we can actually do too completely, but we can get really close).

Nothing can be cooled to a temperature of exactly absolute zero. The temperature of an object is a measure of the average random motion energy (kinetic energy) of its atoms. Absolute zero is the temperature at which all of an object's atoms have been brought to a dead stop relative to each other. This temperature is denoted by the number zero on absolute temperature scales such as Kelvin. Absolute zero is more of a fundamental limit than a reachable temperature. Absolute zero can never be perfectly reached because of quantum fluctuations.
How do scientists cool objects to absolute zero?

So, in reality (doable things) the answer is " it's moving"

I like the phrase pasted onto Galileo: "And yet it moves." ( Or some such phrasing)

 

[Halbhh]

Fun stuff.

“And yet it moves.” This may be the most famous line attributed to the renowned scientist Galileo Galilei. The “it” in the quote refers to Earth. “It moves” was a startling denial of the notion, adopted by the Catholic Church at the time, that Earth was at the center of the universe and therefore stood still. Galileo was convinced that model was wrong. Although he could not prove it, his astronomical observations and his experiments in mechanics led him to conclude that Earth and the other planets were revolving around the sun.
Did Galileo Truly Say, ‘And Yet It Moves’? A Modern Detective Story

 

[TheWhat?]

Given that the universe is expanding and there is no absolute center, yes.

 

[2PhiloVoid]

Is the absolute center of a spinning object moving or stationary?

I was hoping to find more info online about this than I did. Does anyone know? Is there a better way to frame the question in order to get better search results?

... so, did you get it figured out yet, PH?

 

[public hermit]

... so, did you get it figured out yet, PH?

This has been a very helpful thread. I think @Tinker Grey, and a few others, have clarified my confusion. If the center is a mathematical point then the question doesn't apply. But if it's an aspect of the object (has mass?), then it's moving even if ever so slightly, I think.

I honestly wondered if the inner most part of a spinning object was stationary. Now, I'm not quite sure why I thought that, except confusing point with center, perhaps. I don't know.

Edit: I still might have that wrong. Lol

 

[Halbhh]

This has been a very helpful thread. I think @Tinker Grey, and a few others, have clarified my confusion. If the center is a mathematical point then the question doesn't apply. But if it's an aspect of the object (has mass?), then it's moving even if ever so slightly, I think.

I honestly wondered if the inner most part of a spinning object was stationary. Now, I'm not quite sure why I thought that, except confusing point with center, perhaps. I don't know.

Edit: I still might have that wrong. Lol

You've got it right, mostly. Even if a point, it is fun to consider whether it spins. ( I'm not a math purist. Physicist use math like a tool box.)

 

[public hermit]

You've got it right, mostly. Even if a point, it is fun to consider whether it spins. ( I'm not a math purist. Physicist use math like a tool box.)

I'm torn on the idea that a point does not have dimension or magnitude. Lines and planes have dimension, don't they? Aren't those essentially constituted by points? I guess a point has location but no dimension. I'm sure we learned this on one of the many days I skipped class in hs.

 

[Halbhh]

I'm torn on the idea that a point does not have dimension or magnitude. Lines and planes have dimension, don't they? Aren't those essentially constituted by points? I guess a point has location but no dimension. I'm sure we learned this on one of the many days I skipped class in hs.

yeah, it has no dimension, no extent/range. I'm not a math purist enough to care much about strict definitions though. Math is a dirty tool box, kind greasy, with a bunch of tools thrown into it, and I ruffle through it as needed. The outside of the toolbox is old and a bit battered and dirty. It's pretty indispensable for doing stuff tho. So, can an abstraction, a point, spin? heh heh....To me, I tend to want to say 'yes', cause all math that is worth anything corresponds to physical reality at some point

 

[2PhiloVoid]

This has been a very helpful thread. I think @Tinker Grey, and a few others, have clarified my confusion. If the center is a mathematical point then the question doesn't apply. But if it's an aspect of the object (has mass?), then it's moving even if ever so slightly, I think.

I honestly wondered if the inner most part of a spinning object was stationary. Now, I'm not quite sure why I thought that, except confusing point with center, perhaps. I don't know.

Edit: I still might have that wrong. Lol

Yeah, I agree. I think these other posters have more or less (mostly "more," I think) covered the essential bases for this inquiry of yours.

 

[sjastro]

....... Math is a dirty tool box, kind greasy, with a bunch of tools thrown into it, and I ruffle through it as needed. The outside of the toolbox is old and a bit battered and dirty.........

Sacrilege.

 

[chad kincham]

Interesting.

Given the huge spaces between sub-atomic particles I suspect that, statistically speaking there is nothing at the absolute centre of a spinning object apart from an electromagnetic(?) forcefield.

But I could be totally wrong.

OB

Einstein was the start of showing that matter is made of energy, so atoms are basically comprised of electromagnetic energy anyway.

If E=MC2 then M=E/C2

Mass-energy equivalence - Energy Education

 

[FrumiousBandersnatch]

Einstein was the start of showing that matter is made of energy, so atoms are basically comprised of electromagnetic energy anyway.

If E=MC2 then M=E/C2

Mass-energy equivalence - Energy Education

Equivalence is not identity; energy is not 'stuff' that things are made of. Atoms are not 'basically comprised of electromagnetic energy'.

 

[Ophiolite]

The very centre of a rotating disk is stationary relative to an object which is not at the centre.

Does this not assume it is a dimensionless point? Which is a convenient fiction, but has no material reality.
Further, since the spinning object is presumably above absolute zero, thermal vibration will carry atoms across this notional centre, ensuring participation in the rotation. No?

 

[durangodawood]

Does this not assume it is a dimensionless point? Which is a convenient fiction, but has no material reality.
Further, since the spinning object is presumably above absolute zero, thermal vibration will carry atoms across this notional centre, ensuring participation in the rotation. No?

The OP asked about the "absolute center" so I think its safe to consider this an abstract point.

Not sure that reducing the question from a spinning cue ball to a spinning atom makes any difference. What is the "absolute center" of an atom?

 

[sjastro]

Does this not assume it is a dimensionless point? Which is a convenient fiction, but has no material reality.
Further, since the spinning object is presumably above absolute zero, thermal vibration will carry atoms across this notional centre, ensuring participation in the rotation. No?

In this example a point is simply a position in space; for a rotating disk one uses polar coordinates (r, θ) defined by the mapping x = rcos(θ), y = rsin(θ) where r is the radius and θ the angle is the between the radial line and the x-axis.

A point at the centre has the coordinates (0, θ).
For a rotating disk ω = dθ/dt and the tangential velocity v of a point on the disk is v = rdθ/dt (post #7).
A point at the centre v = 0 since r = 0 (and ω ≠ 0), for any other point, v ≠ 0 since r ≠ 0.

Physics is about approximations; the test described in post #5, the Co⁵⁷ source is small enough to be approximated as a point and therefore was in an inertial frame as r ≈ 0.

The Kündig experiment (1963). An 57Fe Mössbauer absorber was mounted 9.3 cm from the axis of an ultracentrifuge rotor. A 57Co source was mounted on a piezoelectric transducer (PZT) at the rotor center. Spinning the rotor caused the source and absorber to fall out of resonance. A modulated voltage applied to the PZT set the source in radial motion relative to the absorber, so that the amount of conventional Doppler shift that would restore resonance could be measured. For example, withdrawing the source at 195 μm/s produced a conventional Doppler redshift equivalent to the TDE resulting from spinning the absorber at 35,000 rpm.

 

[chad kincham]

Equivalence is not identity; energy is not 'stuff' that things are made of. Atoms are not 'basically comprised of electromagnetic energy'.

I showed the equation. M=E/C2

Mass equals energy divided by the speed of light squared.

Matter is solidified energy that can be converted back into energy. E=MC2

Energy can be turned into matter. M=E/C2

Photons in fact are right in the middle between energy and matter, which is why they can be both an electromagnetic wave, and a particle - and why particle accelerators have made both matter and antimatter out of photons - which goes right back to the BB event.

If you check out the BB, the theory is that energy turned into protons, electrons, and photons, then into hydrogen, which became all other forms of matter, and according to string theory, particles are vibrating strings of energy, and according to quantum mechanics, a particle is a collapsed electromagnetic wave, (that has collapsed into a point).

If matter came from energy, then matter IS energy that’s vibrating at a very high frequency, per string theory.

I can show you a dozen of the type of following statements on science and physics websites:

“As Einstein showed us, light and matter are just aspects of the same thing. Matter is just frozen light. And light is matter on the move. How does one become the other?

Albert Einstein’s most famous equation says that energy and matter are two sides of the same coin”.

...” So energy and matter are really the same thing. Completely interchangeable. And finally, Although energy and mass are related through special relativity, mass and space are related through general relativity. You can define any mass by a distance known as its Schwarzschild radius, which is the radius of a black hole of that mass. So in a way, energy, matter, space and time are all aspects of the same thing”.

Source for quote: How are Energy and Matter the Same? - Universe Today

 

[essentialsaltes]

Matter is solidified energy that can be converted back into energy. E=MC2

Energy can be turned into matter. M=E/C2

No, mass and energy are equivalent. There's no need to turn anything into what it already is.

Where you really erred before is in saying that atoms are made "of electromagnetic energy". They aren't. They are made of protons and neutrons and electrons. All particles that have rest masses that have nothing to do with electromagnetism.

Photons in fact are right in the middle between energy and matter, which is why they can be both an electromagnetic wave, and a particle

No no no. Quantum mechanics is why everything can be both a particle and a wave. What distinguishes photons is that they have no rest mass. Nevertheless, they have a relativistic mass that is proportional to their energy.

 

[chad kincham]

Where you really erred before is in saying that atoms are made "of electromagnetic energy". They aren't. They are made of protons and neutrons and electrons. All particles that have rest masses that have nothing to do with electromagnetism.

Tell that to the science that says atoms components, came from conversion of energy (in the form of radiation from electromagnetic waves), thus protons, electrons, and photons cane from energy - and those became hydrogen and some helium, which all other forms of matter made of.

 

[chad kincham]

Where you really erred before is in saying that atoms are made "of electromagnetic energy". They aren't. They are made of protons and neutrons and electrons. All particles that have rest masses that have nothing to do with electromagnetism.

Tell that to the science that says atoms components, came from conversion of energy (in the form of radiation from electromagnetic waves), thus protons, electrons, and photons cane from energy - and those became hydrogen and some helium, which all other forms of matter made of.

 

[chad kincham]

No no no. Quantum mechanics is why everything can be both a particle and a wave

Because all matter came from electromagnetic waves in the first place.

To whit:

“Mass-energy equivalence is the famous concept in physics represented mathematically by , which states that mass and energy are one and the same.[2][3] This idea was not actually put forth by Einstein, but he was the first to describe an accurate relationship for it in his theory of special relativity, where he first wrote down this famous equation. The term is a tremendously large quantity, so this means that a small amount of mass corresponds to a large amount of energy. This equation is only representative of an object at rest, so this energy is called the "rest energy" of an object. The full equation Einstein wrote down includes the energy of a moving object, but the simplified version is still profound.[2]

The implications of such an idea are overwhelming. Mass can be created out of energy, it just takes a lot of energy to do this. In fact, the entire universe was born in the Big Bang when a whole lot of energy was turned into mass.”

Source: Mass-energy equivalence - Energy Education

Thus all matter is comprised of frozen energy which of course can be converted back into energy: E=MC2, and why energy can be turned into matter: M=E/C2.

Particles in atoms are a collapsed electromagnetic wave, that has collapsed into a point.

Ergo, atoms began as electromagnetic wave energy.

It’s like water and ice. Ice is frozen water that can be converted back into water, but water existed first.

Matter is frozen energy that can be converted back to energy, but the energy existed first, per the BB.