speed of light

if something could move at the speed of light would it turn in to light?

could it be that it is moving at such speed which is the only criteria for being light?

There is no condition that something must be visible light in order to travel at the speed of light, it need only have zero rest mass. All electromagnetic radiation travels at the speed of light in a vacuum , and neutrinos travel at almost the speed of light

I aint no physicist, but I do like to think of all things being states of energy, but of note that they are not isolated - rather being built on and within relationships with other energy.

So I like to think a photon (light) carries an electromagnetic interaction, and be made of bosons, which might give it mass through its capacity to interact with its environment, but not classify it as matter (fermions). These all just being names for states of energy in motion... the question then being about understanding the nature of this motion before getting too lost in the math of the labels used to describe the math!?

So I'd say no, but that it might very well go from matter to something fundamental and then the next easiest stable state for all that 'stuff which is no longer stuff' (might as well call it the Force LOL) could be light.... so it might appear that taking it to the speed of light would turn it to light yes, but no because it had actually ceased being stuff before becoming light. There you go, two answers for one question... it does my head in a bit, I think I need to go lay down on a planck now

OB1Shinobi wrote: if something could move at the speed of light would it turn in to light?

You mean something other than light? No, it wouldn't. Nor would it travel at that speed in the first place.

could it be that it is moving at such speed which is the only criteria for being light?

No.

What fascinates me about this sometimes is that the electromagnetic force will expand with light speed just as light particles will move with it, too, but at the same time, gravity will also expand with light speed yet mass cannot ever move with it... Perhaps an indicator that there is indeed only one phenomenon at the root of it all and that what we identified are but special cases of it.

Oh, and also

Adder wrote: ... understanding the nature of this motion before getting too lost in the math...

The math is the nature of those motions. Understanding them is understanding the math. Or, to be more specific, our brains didn't exactly evolve to the end of diving into the complexities of the workings of the universe. So we are, strictly speaking, stuck with the math, because this is the language that happens to be best at describing what we observe. We, in other words, have no means of understanding those things without the math. For our purposes, while the labels are necessary to draw the bridge out of the chalk board and into realiy, still, the nature of those things is indeed mathematical.

Fenton wrote: There is no condition that something must be visible light in order to travel at the speed of light, it need only have zero rest mass. All electromagnetic radiation travels at the speed of light in a vacuum , and neutrinos travel at almost the speed of light

I thought photons had an admittedly very tiny, but still very existent mass.

Whilst we're on the topic of the speed of light though does anyone know why it's not infinitely fast? I ask this because supposedly no time passes when moving at the speed of light so why does it not travel everywhere instantly?

Frost wrote: I thought photons had an admittedly very tiny, but still very existent mass.

Photons are thought of having relativistic mass proportional to their momentum, but the important distinction is that the rest mass is zero. As a photon can never be at rest, it may seem to be arbitrary, but it is an important distinction to make nonetheless.

To your other point: the speed of light in a vacuum is a universal constant. To ask why light speed must be what it is, is like asking why gravity is an attractive force. There may be an answer, or there may not, but I haven't heard of any definite answers yet, and we may never be advanced enough to comprehend the answer should it exist.

Matter has mass when at rest but also relativistic mass which is one of the reasons it cannot be accelerated to light speed.

As for the actual value of the speed of light, that is a matter of definition. If we take arbitrary units and measure both time and distance light travels, regardless of where we take the measurement or how fast our instruments move, the ratio of that distance over that time remains the same: A constant. Since all ratios are real numbers, it can therefore not be infinite. Besides, infinite velocity implies the presence in all places at any given time, which is not true of anything traveling with light speed.

We came to use feet and meters because those units are convenient to us, so we tried to see the value of that constant and found it. Of course, the foot and the meter were previously defined in ways that would be changing on a number of environmental factors, so for convenience's sake we can now use light speed to define them. Normally you would hear that light travels with 299792458 m/s, which makes you wonder how accurate that number is. Well, it is, as it were, perfectly accurate, not because we measured it to be, but because we defined the meter like this. 1m is the distance that light travels in a vacuum over the duration of 1/299792458 seconds, with the second being a multiple of another natural constant.

Frost wrote: Whilst we're on the topic of the speed of light though does anyone know why it's not infinitely fast? I ask this because supposedly no time passes when moving at the speed of light so why does it not travel everywhere instantly?

In Einstein's general relativity e=mc^2 (energy=mass x the speed of light x the speed of light).

If the speed of light was infinite then the energy in anything with mass (even a neutrino) would also be infinite (actually a larger infinity than the infinite speed of light). This would be obviously problematic as if everything had infinite energy, it would also have infinite mass.

The reality is that the speed of light is fine tuned along with many other (so-called) constants to allow protons, electrons and neutrons to form chemical elements and life. In universes with life as we know it - the speed of light is naturally constrained to within a couple of percent of what we measure it as today. If it were different - there literally wouldn't be anything or anyone to measure it.

Within the confines of this theory you are absolutely right when you say the photons arrive instantly - but that is only from their frame of reference. At the speed of light time stops flowing in that frame of reference. However, we as observers of light, not travelling at the speed of light, exist in a different frame of reference and measure them travelling at approx 300,000 km/s.

If c was infinite, no equation involving it would be well-defined. That doesn't mean mass would be infinite, but that the proportionality of mass and energy would not be identifiable. Reference frame dependant energy types lika pretty much all pre-relativistic stuff like mechanics, electricity, thermodynamics, all would have a concept of energy that would be very much quantifiable irrespective of the value of the speed of light.

The speed of light is also not finely tuned for the possibility of the elements we know nor life as we know it. Natural constants are not arbitrary and mutually independant and assuming that universes with different values to those constants are possible, there could be any number of them with vastly different values but with forms of energy nothing unlike the ones we are familiar with and therefore life just as we know it from ours and that is leaving out all the other types of life we probably haven't even dreamt of yet. Interestingly, things like population dynamics and the resulting evolution would be exactly the same no matter what the universal constants would be in the particular instance.

most of this i admit is over my head - i can understand it eventually but it takes a few go arounds so forgive me if i ask the same question again after its been answered

i just want to understand

anyway, speed is relative i understand that, and there is no speed without externality eg something outside of the moving object by which to measure speed

ive read that it is impossible for mass to move at the speed of light - which i can understand as being a rule but i dont understand what MAKES IT a rule

and so i was wondering if, since the rules all change as it
were after a certain speed,
is it theoretically possible that mass actully decreases at a certain speed?
or another way of asking is it theoretically possible that the process of achieving light speed actually transforms mass into light?