Common Sense vs The Theory of Relativity

[Subduction Zone]

The problem as I showed you using the spacetime diagram, is that you can't get to the point where time is 0.

If that photon is traveling for billions of years time then that is time. And if it is traveling it is on a path similar to the 45 degree angle on the spacetime curve, which clearly shows time is involved.

I do not think that you understand a space time diagram. Light is always moving at a 45 degree angle in a space time diagram It is very hard to compress four dimensions down to only two especially when one of the dimensions is not a traditional one.

 

[Tomef]

You can't get to coordinate (0.8,0.6) on that diagram. That would be exceeding the speed of light, which is impossible according to the theory itself.

Please show where on the diagram it is that time isn't there for a photon. Which coordinate are you referring to?

Time isn't anywhere for a photon. Are you saying that by drawing a graph you are redefining what things can and can't do, or something like that?

 

[Tomef]

For instance the speed of light is a constant, so how can photons experience no time or distance? How can something just happen and yet supposedly happen at a different time for someone else? How can two twins ages change just because of travel? To me these are ridiculous ideas.

A thing with no mass will travel at the maximum speed the universe allows, which is the speed of light. For something moving at the speed of light, time has to be zero, as otherwise that thing could move faster. Things with mass can move, using energy, and they move within frameworks of location and time coordinates at whatever speed they can manage. Those coordinates are localised. If you go shooting off from Earth, then change velocity, direction, then the coordinates where you are are localised to that place (as in the earlier post, changes in speed affect the experience of time), not to the place you set out from at uniform velocity. Re. the twins, if one shoots off into space, then turns around, that turning is a change of velocity.

I think it's the last sentence that is the issue, though. The universe operates however it operates. That it doesn't make sense to you means that you don't understand how it operates, that's all. That's true for anyone, really, I mean scientists wouldn't bother trying to find out how things work if they already had all the answers. It's an enormous mistake however to assume that because something doesn't fit into your immediate frame of reference it is therefore 'ridiculous'. That doesn't really mean anything. If you asked someone ask for a loaf of bread in a shop, in French, and the server replied in French and gave the punter a loaf, would you think it was ridiculous that the server gave him a loaf because you didn't understand what was said? That is the kind of mistake you are making.

On the other hand, you can use that sense of not understanding to find out more about how the universe works. You don't need me to tell you there are endless resources for that. You won't learn anything by trying to disprove anything before you have understood it though. You can't negate something until you know what it is.

 

[Tomef]

How can the photon taking two extra years to reach its destination not be experiencing time or distance? It has to be experiencing time or it wouldn't take 2 more years.

It takes 2 more years from the perspective of an observer. The observer experiences the time difference between one event and another, because the observer is not travelling at the speed of light.

 

[Tomef]

You can't get to coordinate (0.8,0.6) on that diagram. That would be exceeding the speed of light, which is impossible according to the theory itself.

Please show where on the diagram it is that time isn't there for a photon. Which coordinate are you referring to?

To invert the idea, in a massless universe, where nothing has any mass, everything would be instant. Movement, communication, whatever else, regardless of any notion of distance would be instantaneous, as there would be no need for a speed limit. Once you have mass, though, a limit is necessarily built into the universe, as otherwise mass moving at infinite speed would consume infinite energy and the whole thing would kaput. Photons don’t have mass, but they exist within a universe that does, hence they have to travel at the maximum speed set by that universe’s fact of having mass. They can’t go any slower, because they have no mass, and they can’t go any faster, because the mass of the universe doesn’t allow it,

 

[TrueBeliever37]

Time isn't anywhere for a photon. Are you saying that by drawing a graph you are redefining what things can and can't do, or something like that?

They try to use a spacetime diagram to prove that time approaches zero as the speed of light is approached. I'm showing you, using that same diagram that that is impossible.

See Figure 5-10 in the book Relativity Visualized by Lewis Carroll Epstein They show proper time on the y-axis, and maximum speed through space (the speed of light) on the x-axis and tell you that its speed through time is zero. That is ridiculous. Being at the speed of light on the x-axis would depict instantaneous arrival no matter what the distance. That is far beyond the 45 degrees which actually depicts the speed of light. As I have said many times, you can't get to those coordinates without exceeding the speed of light.

You can't even get to the (0.8,0.6) coordinates used in the example of Figure 5-9 because that is also faster than the speed of light. That was the example where they said the object travels through 0.8 of a light year of space while aging 0.6 of a year of time. You age 1 year while watching.
Draw in the 45 degree line showing the speed of light, and you will see that object was traveling faster than light. That's impossible.

 

[Tomef]

They try to use a spacetime diagram to prove that time approaches zero as the speed of light is approached. I'm showing you, using that same diagram that that is impossible.

See Figure 5-10 in the book Relativity Visualized by Lewis Carroll Epstein They show proper time on the y-axis, and maximum speed through space (the speed of light) on the x-axis and tell you that its speed through time is zero. That is ridiculous. Being at the speed of light on the x-axis would depict instantaneous arrival no matter what the distance. That is far beyond the 45 degrees which actually depicts the speed of light. As I have said many times, you can't get to those coordinates without exceeding the speed of light.

You can't even get to the (0.8,0.6) coordinates used in the example of Figure 5-9 because that is also faster than the speed of light. That was the example where they said the object travels through 0.8 of a light year of space while aging 0.6 of a year of time. You age 1 year while watching.
Draw in the 45 degree line showing the speed of light, and you will see that object was traveling faster than light. That's impossible.

Actually some particles can travel faster than light for set periods , as I understand it. But anyway, I’ll have a look when I get time. You seem a bit stuck on it though, stepping back and considering the bigger picture (the factors that make it hard to picture what is actually occurring on a simple line graph) might help.

 

[TrueBeliever37]

Actually some particles can travel faster than light for set periods , as I understand it. But anyway, I’ll have a look when I get time. You seem a bit stuck on it though, stepping back and considering the bigger picture (the factors that make it hard to picture what is actually occurring on a simple line graph) might help.

That's exactly what I am showing you. A line on the graph showing speed of light. And proving that it is impossible to be at coordinate (0.8,0.6) without exceeding the speed of light.

You could change the label on the x-axis to be the speed of a bicycle traveling 20mph, and claim it wasn't experiencing any time. But the refutation would be to plot speed at 20 mph and show that the bicycle does experience time.

 

[TrueBeliever37]

Therein lies the problem, you are not understanding time. If at speed C time is zero then it's a draw.

However to an observer photon A reaches its destination before photon B

Relativity remember.

Time isn't zero at speed C.

 

[TrueBeliever37]

Yes, for light it does, but not for the observer external to the light.

I am open to the idea of light being instantaneous. But that is faster than C. You can't have it both ways.

 

[Subduction Zone]

Time isn't zero at speed C.

Correct, Time does not exist at speed C. It cannot even be "zero".

 

[Subduction Zone]

I am open to the idea of light being instantaneous. But that is faster than C. You can't have it both ways.

You are thinking using classical physics. That may be "common sense". It is also very wrong. It used to be "common sense" that the Sun went around the Earth. That the Earth did not move. When one complains about science not following common sense that person will be wrong more often than not.

Distance is compressed to for an observer moving close to the speed of light. This has been directly tested physically.

 

[TrueBeliever37]

Is there anyone out there that can show on the spacetime graph how it is possible to get to coordinate (0.8,0.6) without exceeding the speed of light?

 

[TrueBeliever37]

What have YOU explained?

I have explained that you can't get to coordinate (0.8,0.6) on the spacetime graph without exceeding the speed of light.

Which means that whole idea of an object traveling 0.8 light years in 0.6 years, while you age 1 year while watching, is make believe.

 

[Subduction Zone]

Is there anyone out there that can show on the spacetime graph how it is possible to get to coordinate (0.8,0.6) without exceeding the speed of light?

You can't. Why ask such a question?

 

[Subduction Zone]

I have explained that you can't get to coordinate (0.8,0.6) on the spacetime graph without exceeding the speed of light.

So what?

 

[Subduction Zone]

A space time diagram describes what one can observe. Not where one can go. It is always centered on the observer. For the observer his x position is always x = 0 by definition.

 

[Yerda]

Yes, As that diagram shows you can't have anything to the right of that 45 degree line or you are in an area faster than the speed of light. So you couldn't even have an event at (0.8, 0.6) period.

Events can still happen in that spacetime coordinate. You can't reach the coordinates beyond the line made by the light signal ("outside your light cone") without travelling faster than light which the theory forbids.

Yet for example in the book "Relativity Visualized" by Lewis Carroll Epstein, page 84, Figure 5-9 it says: As speed through space becomes faster, speed through time must become slower. The object travels through 0.8 of a light year of space while aging 0.6 of a year of time. You age 1 year while watching.

That book is available on the internet archive. I'll try to have a flick through it later and see if I can work out what's happening.

For what it is worth, I struggled with special relativity when I first encountered it. I still find it easy to confuse myself with the terms and concepts. It gets a bit easier after some exposure though. Keep at it.

 

[wellwisher]

A thing with no mass will travel at the maximum speed the universe allows, which is the speed of light. For something moving at the speed of light, time has to be zero, as otherwise that thing could move faster. Things with mass can move, using energy, and they move within frameworks of location and time coordinates at whatever speed they can manage. Those coordinates are localised. If you go shooting off from Earth, then change velocity, direction, then the coordinates where you are are localised to that place (as in the earlier post, changes in speed affect the experience of time), not to the place you set out from at uniform velocity. Re. the twins, if one shoots off into space, then turns around, that turning is a change of velocity.

I think it's the last sentence that is the issue, though. The universe operates however it operates. That it doesn't make sense to you means that you don't understand how it operates, that's all. That's true for anyone, really, I mean scientists wouldn't bother trying to find out how things work if they already had all the answers. It's an enormous mistake however to assume that because something doesn't fit into your immediate frame of reference it is therefore 'ridiculous'. That doesn't really mean anything. If you asked someone ask for a loaf of bread in a shop, in French, and the server replied in French and gave the punter a loaf, would you think it was ridiculous that the server gave him a loaf because you didn't understand what was said? That is the kind of mistake you are making.

On the other hand, you can use that sense of not understanding to find out more about how the universe works. You don't need me to tell you there are endless resources for that. You won't learn anything by trying to disprove anything before you have understood it though. You can't negate something until you know what it is.

Here is an interesting paradox. Since all photons travel at the speed of light, relative reference should make all photons appear to be a point, since an object traveling at the of light will appear contracted to a point. So how can photons display a wide range of wavelengths and not have all the wavelength reduce to one point size due to the speed of light?

In other words, if you had a train that was 100 meter long, and it approached the speed of light, based on the correct line of sight, the train would to appear to get shorter, and become a point length at the speed of light. Yet photons, of all wavelengths; long and short photon trains, at the speed of light, do not all get shorter wavelengths, but stay their original wavelength. This fact that they can stay greater than zero; point, tells me that photons are not under the same set of rules as mass and matter. Photons, by themselves, are not under relativity. When around mass and matter, the rules change.

General Relativity; gravity and the space-time profile, can cause photons to lower or increase wavelength. This will create an effect like going faster or slower due to relativity, but the speed of light does not change. In case, Mass is in charge of space-time and it is the space-time profile that is doing this, not the photon by itself.

Mass, due to gravity and the curative of space-time, can alter the wavelength of photons. However, protons, if we shined a billon flashlights to a center will not cause sustain space-time, like mass, unless we add a lot of continuous external energy. But if mass was present, at the center target, the photons would have more of an anti-space-time effect; heat and fluff out the mass density, so space-time expands.

A pure energy universe would not have a sustainable or stable space-time platform. Light coming to together, by chance, will go through each other; waves meet, add and move on. But mass cannot. Both GR and SR are mass dependent, and can attract, compact and stay put. Photons are different. Instead of a gradual accumulation, they can travel through each other, and will want to expand outward, to infinity, unless mass is in the way.

This difference can be modeled as photons being more of a bridge state between space-time and separated space and time; both can act on it and it has the properties of both; energy (enthalpy) and entropy.

 

[TrueBeliever37]

Events can still happen in that spacetime coordinate. You can't reach the coordinates beyond the line made by the light signal ("outside your light cone") without travelling faster than light which the theory forbids.


That book is available on the internet archive. I'll try to have a flick through it later and see if I can work out what's happening.

For what it is worth, I struggled with special relativity when I first encountered it. I still find it easy to confuse myself with the terms and concepts. It gets a bit easier after some exposure though. Keep at it.

I would say NO, an event cannot happen on that spacetime coordinate without exceeding the speed of light. (That event would have no real meaning.) That spacetime diagram is showing time and space/distance. It is impossible to get to coordinate (0.8,0.6) on the spacetime diagram without exceeding the speed of light. Just like it would be impossible to get to coordinate (-0.8, -0.6) as that would have no logical meaning.

ok - when you get a chance take a look. But it's make believe.

Relativity is only true within the bounds of the y-axis (proper time), and the 45 degree line representing the speed of light. So a bunch of those theories they have about seeing the distant past, and people aging different, and an object covering 0.8 light years in 0.6 years while you age 1 year watching, etc. are all make believe.