# Light and Time... doesn't match

Light is emitted by matter which is at a speed lower than $c$. Also, Light travels only at a speed $c=299792458$ m/s. Also, Acceleration $a=\frac{\Delta v}{\Delta t}$. as Light can only travel at $c$, light must achieve $c$ in $\Delta t=0$. if $a=\frac{\Delta v}{0}$ then $a=\infty$.Will it happen in this universe? or is there any medium in this universe? I request everyone to comment on this... Please Don't Ignore... Even if yours or my answer is wrong,comment on this...

6 years, 8 months ago

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Your assumption that $\Delta t=0$ is right but you also assume that $\Delta v \neq 0$ which is not right. Actually $\Delta v$ is also equal to $0$. This is because the initial and final speed are same and equal to $c$.

- 6 years, 8 months ago

how? Light is emitted by matter which is travelling at speeds below $c$. So, if it wants to go at $c$, a change of velocity must occur. so,$\Delta v\neq0$.

- 6 years, 8 months ago

Rule of Mathematics, In Shape $\frac{a}{b}$ , with b $\neq$ 0, so there exists this possibility ! $\Delta$$t$ $\neq$ 0

- 6 years, 8 months ago

in relativity, it is said that light can't travel at a speed lower than $c$

- 6 years, 8 months ago

It has to be a time for less than Be, After All Denominator must be $\neq$ of 0

- 6 years, 8 months ago

that's why i am saying that even light can travel at speeds lower than $c$

- 6 years, 8 months ago

Photons can only travel at a speed of $c$ in which beforehand, for instance when emitted from a atom; they simply didn't exist in the form of a photon. Photons theoretically have no mass as they do not interact with the Higgs field; hence cannot be accelerated.

- 6 years, 8 months ago

OK. so, if it didn't exist in the form of a photon, it must have a travelling speed, that is $c=299792458ms^{-1}$ and according to my knowledge, $a=\frac{\Delta v}{\Delta t}$ as acceleration is a funcion of time, not mass. So, even if its mass is zero, it should have an acceleration. Can't it be?

- 6 years, 8 months ago

I understand where you are coming from and I agree that acceleration is a function of the time, but it is only a representation. When the time 0 the velocity is already c and it did not start from a velocity of 0, it simply didn't exist in the form of a photon as I previously said. The travelling speed that you are talking about was just a form of energy that was suddenly converted into a photon, it didn't exactly have a 'speed' more like a potential.

The acceleration of a particle is not determined by the time, it is determined by its mass or the Higgs field. I haven't studied general relativity in depth though seeming as the photon does not interact with the Higgs field, it can not change its speed. Hence, the acceleration of the photon is $a=\frac{Δv}{Δt}$ where change in velocity is 0, hence acceleration must always be 0 no matter what time, even at t=0.

- 6 years, 8 months ago

So, physically, light isn't visible to us. That means it is a wave and photons are imaginary. Then what is the reason for self propagation of light?

- 6 years, 7 months ago

Now another news... check this out!

- 6 years, 8 months ago

$c$, is the speed of light in a vaccum, light doesn't slow down (de-accelerate), it just travels slower in a different medium. End of story.

- 6 years, 8 months ago

i am talking about light in a vacuum. Not mediums.

- 6 years, 7 months ago