Why can't things go faster than c?

c++ is faster that's why it's called ++

You're mistaken. It's entirely possible for something (stars, for instance) to travel faster than c; it's just that they can never appear to be traveling faster than c because the light from them travels slower than they are moving.

Kek

Have you studied the speed of sound before?

How the molecules of air at atmospheric pressure generates a medium in which sound waves can travel, and the fastest they can travel is the speed of sound. If you were to drive a plane with a powerful speaker, going exactly at the speed of sound, no sound would come out of the speaker, but rather accumulate right in front of the speaker, building power over and over, untill the speed of the speaker reduces and the "sound blast" is released.

Well, the same would happen at the speed of light, but instead of soundwaves, gou have mass.
Mass would compress on itself until it is infinitely wide, perpendicularly to the velocity vector.

So that's why, its literally like a barrier amde of the same mass.

Good question, I don't understand that either.

One answer that I've got was "the universe is a certain space and it has geodesics -- locally shortest paths, we believe that the space has a certain structure and we measure that light travels in geodesics only". I also saw this youtube.com/watch?v=v1GdgD77AQ4 explanation from qm point of view why does the light travel geodesics in a particular case.

t. math major

bump

There's nothing special about light

It just happens that photons are the particles with the least mass

Less mass = can go faster

Because the mass of any object aproaches infinity as its velocity aproaches c.
This means that the magnitude of the force required to accelerate the object also aproaches infinity.
Velocities greater than c of objects with mass are impossibless because their kinetic energy would be greater than infinity

>Less mass = can go faster
Why? Not so obvious argument to me

because as you gain velocity, you gain mass

if your initial mass is big, your will find that once you reach certain velocity, your mass is infinite

if your initial mass is the smallest possible, your mass won't be infinite at the speed of light, but a little bit faster and it will be infinite

A better question than "can something travel faster than light" is "can light travel even faster?"

Related

Common misconception: the speed of light in a vacuum is constant. It's not proper to say "speed of light"- because, the speed of light can be slowed in a gravitational field. Heck, traveling at v=0.8c, there could be a light beam that gets slowed to 0.75c=v because of gravity- voila! You're traveling faster than light!!!! I always like to think that since c is a peculiarly chosen max speed, it is more like the information loading speed of spacetime. It 'predicts' one planck length each planck time...

>Meme++

>I have no advanced degree in physics, my argument is based on half-understood popsci.

speed of light is c in a gravity field in a vacuum

My way of thinking about it is that a property of 'mass' is the ability to have your speed changes at the cost of Special Relativistic effects clapping your max speed.
Objects with no quantity called 'mass' can't have their speed changes, but stay at the speed of light c.

Actually assembly is faster than c

We're limited by the complier. Since most languages are more complex then C their execution speed is much later because of an increase in instructions. That's before you even take interpreters vs compliers. Assembler can be quicker than C but you'd be hard pressed to find someone that can best the gcc.

the speed of a massless particle or a wave in a vacuum is as fast as anything could possibly go. its the speed of causality itself.

Clever.

Machine code is still the fastest

And that's what a lot of engineers really thought too, since planes seemed to just fall out of the sky in terminal dives if they tried.

Bump. No convincing answer yet.

because c is simply the speed of the fastest 'thing' that exists

The idea of relativity is that the laws of physics are identical in all reference frames. We will assume this idea to be true for now, since no experiment has yet shown otherwise.

Since physical laws alone can determine our measurements (further discussion ), then by virtue of this principle, one cannot determine which frame of reference they are currently in. This means that locally everything must function like it does in our everyday experience.

One such experience is the propagation of electromagnetic waves. If the laws of electromagnetism are to be the same, then light must also nessecarily travel at c, with respect to all observers.

This rustles the jimmys of anyone who is used to adding velocities the usual way. Therefore our model of adding vectors in euclidian space must be wrong.

The solution? Velocity space is not euclidian, it is hyperbolic instead. Pic related is art by Master of ceremonies Escher, based on hyperbolic geometry. Note how at any point your surroundings look locally indentical. Adding velocities also makes sense in hyperbolic space, and gives us the relativistic velocity adding rule, which agrees with experiment.

The hyperbolic model however has a limit. The picture (which is actually a Poincare disk representation) must have a finite radius, depending on how "fast" the objects get smaller, moving towards the edge.

The radius of the disk in velocity space represents the maximum possible velocity. Adding one velocity to another can only take you that far. It can be mathematically shown, that the radius of the disk is c.

Explanation why electromagnetic laws require the speed of light to be c, posted by another user a few years ago:

Well, let me tell you the history.

First, like Newton studying gravity, Coulomb came up with a Force at a distance law for charges, F = (1 / (4*pi*e0)) * ((q1 * q2) / (r^2)) which you may notice has a similar form to Newton's law of gravity, two charges (q1 and q2), seperated by a distance (r) exert a force on one another related by a constant (e0, and a factor of pi) e0 is known as the permittivity of space and it's value, long before the speed of light was known, was established through experiment.

Similarly, Ampere came up with a force law for the magnetic force created by two wires with a current I, F = u0/2pi |I|/|r| which is the same basic idea, u0 is also a value that can be physically measured and is called the vacuum permeability.

These values were both measured and the measured values satisfied the force laws to a great degree of accuracy.

Next came Maxwell. Maxwell's laws are a collection of (some) previously established laws of electrodynamics, condensed and reformed into vector notation. The relevant ones are as follows:

Del x E = -dB/dt
Del x B = u0e0 dE/dt

The divergence of the Electric field is equal to the derivative of the negative of the Magnetic field and vice versa (with the permeability and permittivity constants there in the equations).

As a result, Maxwell derived the following:
d^2E/dx^2 = -d/dx dB/dt = -d/dt (dB/dx) = -d/dt (-u0e0 dE/dt) = u0e0 d^2E / dt^2

in other words:
d^2E/dx^2 = u0e0 d^2E/dt^2

and likewise
d^2B/dx^2 = u0e0 d^2B/dt^2

Both of these equations are exactly wave equations with the following form W(x,t), where d^2W/dx^2 = 1/v^2 * d^2W/dt^2, where v is the velocity of the wave

Therefore the velocity of an electromagnetic wave = 1/sqrt(u0e0), which we call c, which is by definition and derivation the speed of all electromagnetic waves in free space.

Because of C has robust tools for memory allocation and management which are much more granular and hands-on compared with that of a garbage collected language.

because space and time are intertwined

because that is the limit of the hardware our universe's computer is built on

C represents Constant, which is what the speed of light is.

If a photon emitter is moving in your direction and sends a burst of light in your direction, it will hit you at a set time.

That time is set no matter what.

If it is moving away from you and the distance at which it begins to emit photons is the same distance it began emitting photons was the same as when it was moving towards you, it will still take the same amount of time it took to hit you when it was moving towards you.

IIRC, relativity does not apply to light because the speed of light is Constant.

said that as you go faster, your mass will increase.

If you have more mass, you need more energy to accelerate.

At the speed of light, your mass is so great, you would need an infinite amount of energy to accelerate even the tiniest bit.

Of course, all that energy is impossible to gather, so you cannot accelerate to a speed that is faster than the speed of light.

If you wish to gain a better understanding of this phenomenon, go to YouTube and rent a PBS documentary called The Physics of Light.

Also, if you wanna know why I spaced all the sentences, it's because I wanted to make it easy to follow.

top kek

>drop a pebble in a pond
>why don't the waves moves at the speed > I < want them to move???

>drop a pebble in a pond
>why don't the waves move at the speed > I < want them to move???

Is this a legit analogy?

It's pretty simple really. Light is a wave propagating in free space. It can even move in a vacuum.

Before Einstein, there was a commonly held scientific belief that light had to propagate through something, namely "ether."

This "ether" was never found through experiment, and was actually disproved (Michelson and Morley won a noble prize for such an experiment).

The conclusion Einstein made was that the medium of light's propagation is space-time itself.

Now we can get to the real answer. The speed of sound is fixed, right? Well, not exactly. It's different under water, in different air pressures, etc. Basically, it depends on the medium it's traveling through. This speed depends on how easily particles can be displaced by sound waves. A "perfect" sound medium would be the environment in which a sound wave travels the fastest. However, such a medium doesn't exist for sound, so there really isn't a maximum speed of sound, just a maximum speed depending on medium.

However, for light, there is a perfect medium: a vacuum. Vacuums have "no" particles in them, so there's nothing that can slow down the propagation of light. Propagation through any material depends on the electric field permittivity and the magnetic permeability of that material, since light is an electromagnetic wave. In high school physics, these terms are dumbed down to the real part of the index of refraction. Now you can see why light goes fastest in a vacuum - a vacuum mathematically has the best values of permeability and permittivity (often called epsilon-naught and mu-naught). The reason for this is a bit circular, since these terms are often defined on the material's ability to support the formation of their respective waves, but the basic idea remains: there's nothing impeding the speed of light in a vacuum, so it goes its fastest speed. There's more to this answer though, but that lies in special relativity which I don't think I have space to explain in this post.

>Also, if you wanna know why I spaced all the sentences, it's because I wanted to make it easy to follow.

Thanks.

But I didn't follow any of them anyway.

There were too many of them to begin with.

I play computer games btw.

You don't understand the concept. Nothing can go faster than the speed of light. Galaxies don't recede from each other faster than the speed of light, the space between them expands. And before you go saying that's just a matter of semantics, it's not.

If you were traveling at 0.8c, and a light beam gets slowed to 0.75c due to gravity, then you would be slowed to 0.6c. Your half-baked argument shows that you have no understanding of the field at all. Don't throw around words like "Planck length and time" unless you actually know the basics of special relativity.

So.. if you want to reach another galaxy.. you just have to BE a galaxy?

BELEIV in urself. u can b anythign!

Light particles are massless. Time, from their point of view, is zero. We can't invent a particle that would have less mass than no mass and therefore travel at negative zero time.

good post

The responses to this thread have went way down in quality over the years. I blame public education.

Why can't things be further north than the North Pole?

>public education
No. It's our culture which elevates ignorance to a virtue which is to blame.

We've reformed education to hell and back and it's only gotten worse. Education reform is not the answer.

Also, I would imagine most science fags have gotten bored of this board by now.

You could theoretically build a mountain taller than Mount Everest at the North Pole (if you REALLY wanted to) and claim, "This is further than the North Pole."

>taller

You don't understand what "north" means.

>Some of the replies in this thread

Is giving retarded answers to this question a meme I don't know about?

Can't space expand faster than the speed of light?

No, but it can appear to. Think about it this way: how do you define "speed"?

Speed is just the distance between two locations divided by the amount of time it takes for the object you're measuring to go that distance.

When you start expanding space, your definition of speed gets a bit messy. Now, that distance is no longer fixed.

So really, two far away galaxies aren't moving away from each other faster than light, the distance between them is increasing faster than light can propagate across it.

Thanks, that helped a lot.

Assembly is faster you idiot

>mass
>infinite
I call bullshit.

In natural units there is no such thing as 2, that's why.

How to destroy the universe:

Get an EM Drive
Let it accelerate until it reaches 0.999999999999999999999999999999999999999999999999999999999999999c
When it hits something, the resulting explosion will be bigger than universe.

inb4 negative mass