Moving in a vacuum? Erm, no.

:laughing:

youtu.be/ioPa1URjZ_Y

Idk about structure, I’m not sure what that would even mean, but a huge part of our interaction with the external world is detecting things without mass. Photons do not have mass.

Rest mass is pure nonsense. Everything is moving.

‘rest mass’ is distinguished from relativistic mass because, in relativistic mass, when something increases in velocity its energy changes. The ‘mass’ of relativistic mass isn’t what you think it is - unless you think you gain mass when you go faster or get warmer.

In the sense that you’re thinking of mass, ‘rest mass’ IS what you think of as mass, whether the thing you’re talking about is actually at rest or not.

Don’t put thoughts in my head, FJ.

Oh whoops, I must have slipped in there by mistake.

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:laughing:

FJ… making Science sound sexual. :laughing:

Cut!

Rest mass = pure nonsense.

Everything is moving.

Aaand action!

“Rest mass” is the quantity of matter an object contains.

A 3" diameter sphere of solid lead has the same mass on Earth as it does on the Moon, even though the Earth and Moon have different motions in space. The only way to change the mass of the sphere of lead is to remove some of the lead from the sphere, or add some mass to the sphere.

For example: A 150 grain bullet has a specific mass, and that mass is the same whether you hold the bullet in your hand, or you send the bullet out the barrel of a gun at 3,000 Feet Per Second. There is nothing added to the bullet, and there is nothing taken away from the bullet, so it has the same mass.

The “nonsense” is all Einstein’s, where he claimed a frame of reference can be considered “at rest”, but he has no way of determining that BS.

For example, according to Einstein, if you are inside a box in space, the box is a frame of reference that is at rest. So if you send a light from the center of the box it will reach the center of all the walls at the same exact time.
Here’s the BS part: If you accelerate the box and increase the speed of the box in space he claims the light will again reach all the walls at the same time. He MUST say that in order for his BS theory to be consistent that the speed of light is constant in a frame of reference.

The problem comes to light when a scenario such as MD’s BOX PROVES that it is IMPOSSIBLE for the light to reach all the walls at the exact same time if the box has motion in space, or stated quite clearly: if a box has an absolute velocity greater than zero it is IMPOSSIBLE for Einstein’s second postulate to be correct. That means one thing, we must throw his piece of trash theory in its appropriate place, the dumpster!!

Rest mass is only apparent from the point of view of an observer (subject to time) moving with the flow of the grandwave.

Your box is merely a thought experiment. Einstein’s second postulate is well established/confirmed by … stuff.

Again, unless you think you gain mass when you start moving, “rest mass” is quite literally synonymous with “mass” for most use cases. You’re using a distinction that I don’t think you quite understand.

Do you gain weight when you start moving?

Rest mass has nothing to do with a point of view. The mass of an object does not change depending on who you ask. A bullet has a mass, and that doesn’t change just because someone travels at half the speed of light past the bullet.
You are trying to claim that an object’s mass changes depending on how fast you go. Absurd.

My box is not simply a thought experiment, it is the very definition of distance and time.

If you draw a circle on a piece of paper with a center point, is it simply a thought experiment that the distance from the center to the circumference is the same in all directions? It is a FACT that the distance from the center to the circumference is the same in all directions, and claiming that is just a thought experiment and doesn’t mean anything is total nonsense!

My box is the very definition of how distance and time according to light manifests over time. The equations are there, which are mine, and they are flawless! Prove me wrong.

What is proven wrong by the box is Einstein’s second postulate, because in the box the light hits the x receiver and the z receiver at DIFFERENT TIMES, even though the distance from the center to those receivers in the box are exactly the same. Recap: Same distances, but DIFFERENT TIMES, so the speed of light in the box is DIFFERENT to each of the receivers, which proves Einstein is FOS!

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It sounds like Ic might be talking about force… for e.g., the higher the speed of a car having more impact.

That’s actually correct, that’s more or less what “relativistic mass” means. Relativistic mass increases with velocity, because it’s basically proportional to momentum, or force as you say.

And the type of mass that we talk about that doesn’t increase with velocity is called “rest mass”.

What objects would those be? photons and such…

Anything. Photons. MagsJs. Flannels.

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Wouldn’t a running MagsJ or Flannel have more impact/momentum-force, if we ran into someone/something… American football tackle style?

When you’re talking about the mass of any object, you can talk about it’s relativistic mass or its mass at rest. They are both valid concepts for any object, as long as you know why you’re using one and not the other.

I don’t know what American football is though. You mean hand egg?

That’s like asking what objects have weight. All objects have weight. But “weight” is a slightly different concept than mass. The “weight” of an object changes depending on where you “weigh” it but its mass stays the same no matter where you weigh it.

The mass of a bowling ball is the same on Earth as it is on the Moon, but the ball will weigh less on the Moon because it requires less force to stop the ball from falling towards the center of the Moon compared to the force required to stop the ball from falling towards the center of Earth.

It’s like someone is pushing on the ball towards the center of both the Earth and Moon, but the person pushing on the Moon is not pushing as hard as the person on Earth, so the “weight” of the objects will be different because the force is different, even though the mass is the same.

That is more MOMENTUM, which is mass times velocity. Given the same mass, a greater velocity will increase its momentum, which equates to a greater force of impact. It is a greater force at a greater velocity because at a higher velocity it takes more force to stop it than it does for a lower velocity.

It is easier to stop a bullet traveling at 10 feet per second than it is to stop a bullet traveling at 1,000 feet per second. The reason that increasing the speed of a given mass bullet will go through thicker targets is that it takes more force to STOP IT. If it doesn’t stop as quickly then it will obviously penetrate a greater distance, hence go right through the target at a higher velocity. The mass didn’t change, the velocity did.