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Light speed theories
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 ianuk29-May-12, 14:44

Light speed theories
Here's another that many people start off forgetting the basics.
Many scientists convey their theories about light speed and how nothing can travel faster etc. Then they show
diagrams with two light sources travelling toward each other and claim that the approaching lights would
experience the other travelling at 2 X light speed...... How can this be if nothing travels faster than light?

Well here is the absolute simplicity of it.

Most people omit a very important part of the description about light.

"Light travels at 186,000 MPS from its source."

It is sometimes suggested that if the light source was to travel near to light speed the light itself would slow
down. WHY?? OK, the light is travelling near to light speed, but in relation to what???? From what stationary
base point is the speed calculated (Remember most of space is empty)

Light speed IS constant and is measured from source. Whatever that source is doing itself has no bearing on
the light that is emitted.
 chrisforbes2131-May-12, 15:24

light speed is a measurement
I would not say that travelling at light speed is the absolute fastest you can go, its more just our
current understanding of it, its a bit like man can't fly, or go through the sound barrier or travel
mach5, they are already looking at mach10 but there is gravitational issues but that does not
necessarily apply when in space. I like to think about jet streams, so there might also be these
type of jet streams but on a much larger speed scale in space. Being one who loves to break
with conventional theory. Science and theory tends to go with trends it takes an
unconventional mind to go against the heard and the long lists of famous people who doubt you
wrong only in time to be proven right. There is one constant in the universe is the laws of
mathematics unfortunately I think even our greatest minds in this field only see 25% of the big
picture.
 riaannieman01-Jun-12, 03:41

I agree with one thing, at least.
Maths. Pure, simple and cannot lie. I love mathematics. It is unfortunate that I am not as good with maths as I would like, but once I grasp a concept, it seems so obvious. The best science of them all.
 chrisforbes2115-Jun-12, 19:22

the speed of light
is only a theory in our understanding of speed it is what it is, I guess when we learn more the
speed of light will not be definitive
 ianuk16-Jun-12, 01:16

Assuming more
Whilst we are limited in our knowledge of these things, this does not mean necessarily that there is more to
know. Electromagnetic radiation propagates at a set rate dependant upon the way the energy reacts with itself.
Because we don't understand why does not mean that it may be possible to alter this. Speed of light IS definitive
and is relative to its source.
In this finite universe, (in-so-much-as all that is within it is defined and tangible), there will be always be a limit
to the amount of knowledge and physical matter that exists. The only part of the universe that is unmeasurable
and limitless is space itself.

Anyway - back to chess now - gotta learn to win more.....
 chrisforbes2116-Jun-12, 05:54

assumption is the definition of the word
its only hypothesis there is no reason why there cannot be other hypothesis

If we can propel a particle at almost the speed of light in a particle accelerator why not a larger
particle? say large enough to carry a tiny camera! at almost or even half light speed we could
reach the nearest stars in say 5 or 6-years. Snap a pic and see if there are any exoplanets or
moons. Considering how long it going to take to get that spacecraft we sent to Pluto, or the
ones we sent
past Neptune, it does not seem so long!! just a thought!
 chrisforbes2116-Jun-12, 06:53

that is going to be some tube
Yes theoretically you could do that, it does seem practical its going to be a big tube pointing
upwards to get the speed to hit that thing into space. Great Idea!!
 riaannieman16-Jun-12, 07:13

Gravity
I'm not a physicist, but I would think that we should be able to use gravity as a slingshot to help build momentum. It is the one force in nature that is found everywhere, and it is very strong. Just a little faster, please, than Voyager, that only left out system a little while ago, after spending years traveling. I would love to know if stars like Alpha Centauri, Barnard's Star, Sirius and others, have habitable planets, that are in the Goldilocks zone.
 chrisforbes2116-Jun-12, 07:19

perpetual motion
My mate who is a serious physicist keeps telling me perpetual motion is impossible but I think it is
achievable. That slingshot theory is part of it. When you look to ancient history its amazing
that they found Sirius B. en.wikipedia.org
 ianuk16-Jun-12, 07:23

on and on and on and on and on
Perpetual motion does indeed exist in nature. Consider the electron orbiting its nucleus. What is it that keeps
that going???
 chrisforbes2116-Jun-12, 07:26

it does exist in nature
Thanks Ian because every time I talk about it people tell me its impossible but my gut tells me it
is possible, thanks for your confidence in the idea
 ianuk16-Jun-12, 07:59

Superconductors
These are possibly the key to obtaining some kind of 100% energy transfer. Research has been going on for a
while in an effort to get superconducting material at room temperature. Once they can master that one then we
may be a little closer to solving our energy problems.

one way
Un-manned nanoprobes

Near-lightspeed nano spacecraft might be possible within the near future built on existing
microchip technology with a newly developed nano scale thruster. Researchers at the University
of Michigan are developing thrusters that use nanoparticles as propellant. Their technology is
called “nano-particle field extraction thruster,” or nanoFET. These devices act like small particle
accelerators shooting conductive nano-particles out into space.[20]

Given the light weight of these probes, it would take much less energy to accelerate them. With
on board solar cells they could continually accelerate using solar power. One can envision a day
when a fleet of millions or even billions of these particles swarm to distance stars at nearly the
speed of light, while relaying signals back to earth through a vast interstellar communication
network.
 ianuk19-Jun-12, 15:20

What a super idea, but....
That is an interesting concept, except that if you are travelling near to the speed of light any data sent back to
Earth will be travelling at light speed MINUS forward velocity. Thus any transmission received on Earth will be at
a much lower frequency. It is a fact of physics that the lower the transmitted frequency is, the short the distance
it will propagate. Therefore more energy will be required to send the signal back. As the travelling craft tends
toward light speed then the energy required will tend towards infinity.
ianuk
14-Jul-12, 05:19

Deleted by ianuk on 14-Jul-12, 06:10.
 ianuk14-Jul-12, 06:10

Kick this one into the light again (Pun intended)
I question the logic regarding light speed.
When we talk of travelling through space we are unwittingly relating it to the Earth as a point of reference.
Lets theorise on a point deep out in space. A small rock that is "travelling". What is it that makes us assume it
is actually travelling? Well its position is mapped along with all other objects, stars, planets that are also
mapped.
The positional relationships between these objects is used to determine their motion through the cosmos. But
only in relation to each other. Who is to say which of these is travelling in which direction and at what speed.
To another object somewhere else they will all assume a different trajectory and velocity. But to each of
those objects individually it would seem that all the others are moving. Speed of motion and indeed light
speed is always measured from point of source. How would is be possible to travel at any other speed to the
one at present and how could you possible say how fast that is anyway. Even if you could measure from a
fixed point how can you be sure that the fixed point is not the one that is moving?
As far as travelling faster than light. Of course its possible, but there would be no change in any of the laws of
physics. Here's why.
Lets assume you are positioned adjacent to an object that is radiating a light source in the direction you are
facing. That light will be travelling away from you at light speed. Suddenly the object begins to travel in a
reverse direction away from you at ¾ light speed. The light you are observing is now travelling away from you
at ¼ light speed. Now you begin to travel forwards at ½ light speed relative to your original location. You will
now be travelling faster than the light you are observing by ¼ light speed. Are you now travelling faster than
light?
I am even finding E=mc² a little hard to comprehend now. As I understand it, the faster you go the more
energy you need to accelerate. WHY? Newtons 1st law covers that one. Stop accelerating and you remain in a
constant state. Add more energy and that state will change. Whilst it may be here on Earth that the faster you
go the more power you need to go faster, (that being due to wind resistance) out in space there is no
resistance or friction, so any energy input will have a direct influence.
 shamash14-Jul-12, 07:49

the velocity of info maxes out at c
actually in Physics the maximum rate of information transfer is limited to the speed of light.
 texasron14-Jul-12, 08:39

The silliness of relativity
I am reminded of a Limerick my Dad once told me:

There once was a fellow named Dwight
Whose speed was much greater than light
He set out one day
In a relative way
And returned on the previous night

Of course, such silliness is just that...silliness. Look at the special Theory of relativity itself

E = M C-squared

where
E is energy
= is the equals sign
M is mass and
C-squared is the speed of light squared

So why is the speed of light given the letter C? I let the king of all knowledge (Google) research it, and it seems that it comes from the Latin word "celeritas" which means swift. In Texas, any word that ends in RITAS means it is a frozen drink made with tequila, likke margaritas or strawberryritas. Now, if you're talking a frozen tequila drink make with CELEry...count me out. Maybe the Speed Of Light should be given a more appropriate label...like (S.O.L.)

Although SOL could be confused with the common name for our mother star the Sun or Sol. But S-O-L also has an American expression tagged to it meaning "Sh*t Outta Luck" (I hope that passes the censors)

Anyway, I whole-heartedly appreciate these kinds of discussions. I like the feeling of headspins. When it comes to completely understanding physics though, I am truly SOL. LOL!

 ianuk14-Jul-12, 09:27

Someone once said.
I read this somewhere in a Peanuts cartoon.

A kid in class asks "If light travels at 186,000 miles per second, why are the afternoons so long."
 riaannieman14-Jul-12, 09:47

Back to google, for a moment
Hey guys, have a look at my profile, then you'll understand this:

And then, anything made with tequila, makes me happy...

So seriously, how did Einstein figure out that energy is equal to the sum total of mass times the speed of light squared? It must have been an epiphany that equaled Eureka! So probably, that's why I'm not a physicist. I would give a lot to experience such an epiphany. It must have been a higher high than any drug. I've never done any drug in my life, besides some alcohol and cigarettes (that stopped more than 8 years ago). My best high like that would be when I did my first static line parachute jump, and then my first freefall a couple of weeks later. Well, at least I must have felt like Newton at the time.

I've read a little about physics during the last couple of years. It is one of the most interesting subjects to study- along with maths, biology, evolution, astronomy, geology, politics, religion (or the lack thereof), global finance..... I wish often that I was capable of the understanding, study and pursuit of physics. There are several limits to my problem: time and money would be the first problems to overcome, but I am realistic and know that it is a field that few of us will really be able to contribute positively to.
 ianuk14-Jul-12, 10:16

Blackle.com
Nice idea - but the saving depends a little on whether you have an LCD or LED monitor.
 riaannieman14-Jul-12, 10:50

Blackle.com
LCD! That is what my laptop uses.
 ianuk14-Jul-12, 12:48

LED / LCD
As I understand it, LED generate light for each pixel used, thus a black screen should use less energy.
However, LCD rely on a backlit screen which then used LCD filters to block the light as necessary. The backlight is
constantly on.
 astinkyfart14-Jul-12, 22:38

Until
the laws of physics as we know them change, as far as we are concerned traveling faster than the speed of light or even the speed of light itself is impossible.
 ianuk15-Jul-12, 02:33

Impossible question
I think we all tend to lose sight of reality.

So much reference is made to the speed of light. But how are we quantifying it? We speak of speed as
something
that takes us from here to another place. Currently we use the Earth as a reference because we are able to
measure it and chart our progress as we travel. In space there are no reference points. At least none we can
categorise as "Stationery".
If we shine a light toward the sky we claim the beam is travelling away at light speed. But if we were to travel
beside it at the same speed, quite apart from not being able to see it any more, it would no longer be
travelling
away from us. Also on our journey, far away from anything else and assuming no external or internal
influences,
our journey will have a constant vector and velocity. In fact with no tangible or measurable inertia we might
just
as well be motionless. In fact, relative to the light beam beside us we are!
The bottom line here rests heavily on the word "relative" and will always require some kind reference to make
any measurements.
We know from astronomical measurements that there are galaxies travelling away from us at tremendous
speed.
Or is it US travelling away from them? Or are they travelling at light speed and us at half light speed?
Of course there is another, perhaps worrying, thought. If we do achieve high velocity, even if its just a small
percentage, then all our navigation could be thrown into disarray. As velocity increases there would be
noticeable
red and blue shifts in the visible spectrum. At really high velocities this could cause current known and charted
constellations and references to disappear from visibility. Likewise, new stars may become visible. To go into
an
new adventure without a map would be perilous to say the least.
 chrisforbes2115-Jul-12, 02:42

for me it is a bit of exploration
It comes back to my world is flat syndrome and for me the speed of light runs on the same
principles and just because a charismatic guy called Einstein says that is the way it is I do not
believe it.

en.wikipedia.org

I like a man or woman that goes on a journey
 chrisforbes2115-Jul-12, 02:44

to clarify
even Einstein admitted it but he was on his death bed
 astinkyfart15-Jul-12, 07:52

We have
come a long way since Einstein, even with the particle accelerator his theory holds true. We cant even make a microscopic speck of matter go the speed of light. Right now it is not possible. So as far as we are concerned it is not only a theory but a fact of physics. It is as much a fact as gravity.