Suppose a light ray travelling near a black hole, which has so much gravity that the escape velocity is twice the speed of light, got caught in its gravitational field. Will the light travel at the speed of light or travel at double the speed of light?
Similarly what happen to other objects that get near, at what speed does this travel?
The Speed of Light is the Speed of light....It doesn't matter if it is 166,000 miles per second or 300,000 miles per second...
Since Theoretical Physics, considers the Speed of Light as one of the Universal Constants ... Therefore, Theoretically, it is impossible for a ray of Light to Travel faster, than its Totality's Constant.
But Theory, after all is Theory, and there are quite a few Forms in Nature, which in the Relative Sense, Oscillate, a couple of billion times, per second between the two extremities of Oscillatory Motion.
These Particulate "entities" in Reality, are travelling far beyond Theoretical Physics' Limit of the assumed Universal Constant, of the Speed of Light, represented by the known Electromagnetic Wavelengths based Photonic Motion.
Therefore, Theoretically, a Ray of Light, [Electromagnetic Radiation] under the stated Circumstances, cannot Exceed the Constant, but these other Phenomenal entities, travel millions of Times Faster than the Theoretical Absolute Speed, of Light.
How these do this, is in the Truth, that matter ,,. whether in State of Vibrating Particles, or Electro-Magnetic Radiation, are also, a Part of un determinable Extant of Creation ...
These indeterminate states are Governed in the Existential, by a distinct Behavior of the Created Form ... Moving in other than the Known Modes of
Radiation, and Motion.
Did you drive, or bring your lunch today?
I suspect that this is going to be a troll so that you can say;
"Aha, but energy, relativity and black holes don't exist because they can't be held in the palm of your hand or put in a shoe box. And I don't believe in E=MC2 or anything that I didn't learn in primary school physics lessons."
Either way, unless you're seriously wishing to discuss this and haven't already made up your mind, I'm not taking the time out to explain.
You don't have a great record on these things, jo.
Wrong forum perchance? Unless you wish to debate whether or not God can travel faster than light.
" And I don't believe in"
That one thing you got correct, I don't BELIEVE in, that is what you do. I didn't intend to post this here. As we are talking about religion I posted it in religious forum, though I typed it here first. I cancelled it, may be I clicked the submit button.
If I want to worship something, there are lot many churches in the locality!
How do you know, I might live in Sudan?
OK Jo, look. There have been many many times during the development of science when someone has come along and blown the accepted theory out of the water with a peice of brilliance. Examples abound.
However, and almost without exception, these people have had a strong grounding in the science in which they have had the breakthrough - they have immersed themselves in the accepted theory and then slowly imparted their knowledge and skills in pushing the field forward.
You have no such grounding. You just come on here and spout off about science being a religion and the argument to authority fallacy. This isn't how we progress in science, or as a species generally.
If you don't know or understand the original physics, then you can't have a point of view which is valid. Similarly, if you are just attacking something based on wrong premises (i.e. the dictionary definition of something), then your point of view is not a valid one. Finally, unless you yourself have something to offer in terms of a valid alternative (which I've explained is going to be difficult because you don't understand the science), then your point of view is not valid.
At the moment your point of view is as valid and likely to be listened to as a drunk who's burst into an operating theatre and started demanding the surgeon "do things differently".
"How do you know, I might live in Sudan?"
I was talking about me! And in your forums you repeatedly say yo are from Europe!
"This isn't how we progress in science, or as a species generally."
Well the progress part is subjective!
"If you don't know or understand the original physics, then you can't have a point of view which is valid."
But science is an explanation even a child should understand. It is technology that is difficult, it is technology that need proof, it is technology that is done with trial and error.
"Similarly, if you are just attacking something based on wrong premises (i.e. the dictionary definition of something)"
Through out, I have used only definition that is valid in all circumstances and is consistent. I have not changed any of my definition to explain anything. But in relativity, you never define, all words are used interchangeably. You might note that, "in the brief history of time", Hawkins never defined "time". Time, space, energy, exist, dimension, coordinates are terms you people never define and use all the meanings found in a dictionary and even interchangeably(like dimension and co-ordinate). It will be good for you to remember that, till now you have not come up with a rational explanation for any of the terms, and your friend Beelzedad said he uses the common meanings. So why do you accuse ME of doing that?
"Finally, unless you yourself have something to offer in terms of a valid alternative (which I've explained is going to be difficult because you don't understand the science), then your point of view is not valid."
There is a major problem. You might never have seen people, I presume! The majority in the world subscribe to religion. They do it, not because the teachings are rational or attractive, but because of an emotional necessity. So if you take religion out of such people, you have nothing else to offer. However rational be your explanations, it can never substitute for emotions. Does that mean you should continue advising religion to emotionally immature people.(These are the people who may take to alcohol, you will not advise that either!).
Now Bill Gaedes EM rope theory is a rational explanation, I think, though his language is a little difficult to digest. Try that.
"demanding the surgeon "do things differently"."
Well sometimes we are forced to do just that!!
So, you are a sock puppet of Bills, that would make sense.
Not like you mocking up Einstein.
He define all words and I found no contradiction yet, unlike relativity. I said, I think rational, as so far I haven't found any contradiction, but I haven't completed reading his book to give a final opinion!(And I'm re-reading, the relativity stuff along with it, just feel like reading bible again)
"I'm not taking the time out to explain"
Don't say about that which you can never do!
A beam of light traveling through water or other medium with a refractive index greater than 1 will travel slower than light traveling through vacuum.
No, the question is not whether light can travel faster than "c" through a medium,
The question is, is that black hole able to pull the light faster to its, er, center, through vacuum!
You have only offered the escape velocity in your question, hence you have not offered anything that would question whether or not the light would be "pulled" towards the center of the black hole at faster than light speeds.
It is supposed that light does not come out of blackhole as the escape velocity escapes the speed of light. That is the blackhole is pulling the light back. What happens if the light was travelling towards the "hole"?
Escape velocity refers to something that can escape the gravitational field of an object without further need of propulsion. Your use of it in your OP is not required and does little more than confuse.
The light would get absorbed by the black hole.
What is the limiting factor if the 'force' of gravity is more?
Gravity has nothing to do with the speed of light, hence cannot invoke a "limiting factor."
Still it can prevent light from escaping, by limiting its speed!!
Nonsense, gravity does not limit the speed of light.
Clarify your question.
Are you talking about the speed of light being limited or are you talking about light being limited from escaping the black hole?
Ok...lol.. I'm a beam of light traveling at my supposed max speed in a vacuum.
I am able to compress my "photons" into a concentrated laser beam and I aim it ahead and "energize" it to max cap. Will the beam leave the source (me) and race ahead at double my speed,or will it not respond because I, the default "beam" of light am already travelling at my max speed?
Jo has no answer for me that makes sense.
"Jo has no answer for me that makes sense."
I have no answer!
If there is a speed limit, I think, the apple will be in your hand.
If an apple is a particle, there is no reason for a speed limit.
If it is a wave, the medium limit it.
Frankly I don't know might be a better answer.
Photons don't really "compress" - however adding energy will cause them to increase in frequency, proportionally.
The photons will leave the source traveling at the speed of light, which you can measure whether you are traveling at near light speeds or if stationary, at rest.
Whether the source of light or the observers measuring it are stationary or moving will in no way influence the speed of the light itself.
I know that :
"I" am already travelling at the speed of light.
I think it is confusing to all of us.
I've got a friend who's a physics nut.
I'm gonna ask him.
Thanks guys. I think Jomine gave the right answer: "I don't know."
Hahaha I expect you aren't, but I am. :
Your "explanation" then, is adequte for you, but leaves me in the "dark." lol
I understand this: "Whether the source of light or the observers measuring it are stationary or moving will in no way influence the speed of the light itself."
That doesn't answer my question.
I'm gonna check it out with my "physicist" friend and get an answer based upon the laws of physics.
Thanks for the "energetic" effort to try to "brighten" my day with a "guess." :
I hope the "bunny" was good to ya! :
It should answer your question. The reason why the motion of the source is irrelevant to the speed of light is because the properties of space are what inhibits light to move any faster.
In other words, particles with no mass, like electromagnetic radiation, are subject to the Permittivity (the resistance to an electric field) and Permeability (resistance to a magnetic field) of space which controls its speed through it.
Thanks for the insult to my intelligence, that brightened my day, too.
We are willful creatures Beelz.
One can only be "insulted" if one allows oneself to be.
Try using that "will" and never ALLOW yourself to be insulted.
It sure works for me.
Have a great day ya "ornery" cuss...:
Yes, I see what you mean, that one should have some "self control" over oneself because they understand such oafish and half-witted insults shouldn't really bother them and that it says more about the one who is spouting them.
Or, are you implying that not allowing such elementary and one dimensional remarks to bother me is reason to permit and encourage others to spout them?
"properties of space are what inhibits light to move any faster."
Now a days, space is having "properties" too!
Great, hope it does not walk away, when when your universe expand to its maximum.
"(the resistance to an electric field) and Permeability (resistance to a magnetic field) of space which controls its speed through it."
Like the wall you try to penetrate, prevent you from penetrating?
When will you learn that space is "nothing", and nothing never control anything!
Nowadays? Space always had properties.
Strawman fallacy concluded with an Argument from Ignorance fallacy.
"Space always had properties."
Argument from Ignorance fallacy
“are subject to the Permittivity and of space which controls its speed through it.”
"Strawman fallacy concluded with an Argument from Ignorance fallacy. "
Thanks for giving that example
Photons have no rest mass. You can only accelerate or decelerate something with rest mass. Hence photons must travel at the maximum speed. This speed is a parameter of space itself - calculated from measurements of the permeability and permittivity of free space and there is nothing anyone can do to change that.
If gravity is preventing the light from escaping, and if its speed is not affected, then what happens?
Is not speed the distance traveled in a sec?
Irrelevant, Moffat's theories are regarding the early universe, nothing to do with what's happening today.
Yes, and we'll just take your word for it.
"In 1992, Moffat-a now-retired University of Toronto astrophysicist-hypothesized that light may have traveled faster in the early universe, then slowed to its present speed."
http://www.weeklyscientist.com/ws/artic … moffat.htm
Well it's not my fault you don't know the implications of Moffat's work. João Magueijo William Heinemann,London, 2003. But I sent you a link to that already, it seems a waste just talking to you, when you have already demonstrated your lack of intellectual honesty.
I will probably open a new thread about it so that other people can take a look at it and discuss it intelligently. But for now I'm going to Nice and will spend spring there. goodluck trolling and copying old factoids from text books.
I read Moffat's work and the link you provided. Moffat's theories have to do with the early universe. That is a fact.
Please do start that thread. This should prove to be quite entertaining.
Of course, you're going to have explain what Moffat's theories have anything to do with the speed of light today. Good luck.
I'm sorry but my flight is in two hours.
There was a thread about Penrose and the pre-big bang ripples and the variable light speed was discussed then.
In Meguillo's work, he described that light does not fall into black holes, but is suspended there. Remember the discussion about we never really approach zero but we can go towards it? get two neurons and connect that.
Ah, so you actually won't be starting that thread?
it's like you're a think wall of lead.
Impossible to measure since at the speed of light, time stands still, accoring to mr. einstein.A measurement could only be taken if time is moving.
Time runs slower at the speed of light but does not stop.
I believe time dilation leads to all measurements of light's speed in a vacuum to be the same no matter the reference frame.
No. It's can't exceed the speed of light.
What can happen, though, is that the frequency of the light increases - where light would "want" to travel faster the frequency shifts towards the blue. This increases the energy of the light the same amount that a speed shift would have.
There is nothing in universe that can travel faster than the speed of light. The speed of light is the speed limit for universe. Albert Einstein and other physicist have proven that already. Light is pull into a black hole like all matter that exist in the universe because of the duality of light, that is, light is both a wave and a particle. A black hole cannot pull anything faster than the speed of light because it is the force of gravity that is pulling all the matter into it and the maximum speed of gravity or gravitational waves is equal to the speed of light. Remember space and time is the same thing. This is why time slows do or stop near a black hole to keep anything from traveling faster than the speed of light.
"There is nothing in universe that can travel faster than the speed of light. The speed of light is the speed limit for universe."
Well light speed taken as 'c' you mean? Then light itself travels faster in certain medium. Forget the other stuff "tachyon" which nobody knows.
"Albert Einstein and other physicist have proven that already. Light is pull into a black hole like all matter that exist in the universe because of the duality of light, that is, light is both a wave and a particle."
For a wave to occur, there should be a medium. What is the medium of light?
"A black hole cannot pull anything faster than the speed of light because it is the force of gravity that is pulling all the matter into it and the maximum speed of gravity or gravitational waves is equal to the speed of light"
Gravity pulling ok, but what has it to do with "speed of gravity". The force of gravity depends on mass, isn't it? The the more the mass the more the pulling!
"Remember space and time is the same thing. This is why time slows do or stop near a black hole to keep anything from traveling faster than the speed of light"
Till yesterday space was nothing and time was what I read from a clock. How come they became one and the same "thing"?
nothing in this universe can move faster than the speed of light. till today humans have traveled at a maximum speed of 25,000 mps in Apolo 10. And the fastest motion that is going on Earth is in CERN, Geneva where pi-mesons are accelerated in large circular tunnel. they are being accelerated till the particle starts taking 11,000 circles of the tunnel in one second i.e they starts moving approximately with the speed of light (99.99%). But they never cross this limit. not even they reach the speed of light.
If we look a Chandreskar's work, we see that his calculations show that a star with a mass of at least 1.44 times the mass of our sun is required to form a black hole once the star has gone nova.
The volume of the sun is about 1.4x10^18 cubic kilometers, about 1,300,000 times that of the earth. A star that will become a black hole must have at least 1,870,000 times the volume of the earth in order to form.
A black hole forming from that mass would be less than 10 kilometers in diameter. Hence, all that mass of 1,870,000 times the earth is being compacted into an object less than 10 kilometers wide.
The sun's diameter is about 1.4 million kilometers. Even if you were able to stand on the surface of the sun, you would be squashed flatter than a pancake due to the surface gravity.
Even if a light ray were to come within a half million kilometers of a black hole (less than 10 kilometers diameter), it would be undergoing the same effects as if it were hitting the surface of our sun.
Hence, the effects of the light will continue to be dramatic as it makes it's way closer to the black hole, because even though the black hole is less than 10K wide, it's gravitational field is still the same as if it's progenitor object were still there.
It's plausible that when particles are super accelerated beyond normal, that they no longer act as they would under normal conditions, and therefore, are changed. So I don't think super accelerated photons are going to able to remain identified as photons in such conditions.
Kind of like burning wood. You introduce other factors acting upon it like burning, and the particles aren't destroyed, but they are changed.
Will they travel faster if the gravitational pull by the hole is greater?
That's a good question. You would think so, but I think there are factors in science that would have to be considered to accurately determine that. I have no idea what they are really, but they are learning now that the further out in space you go, light actually "bends", sort of like there is a horizon line in the universe. So not everything is as it may actually appear.
If the particles you mean are photons, then no.
Look at the response from wilderness concerning the blue shift back on the previous page.
Let me give you an example of the depth and breadth of my understanding of physics i.e.
..."if I and my flashlight are travelling forward at the speed of light and I click my flashlight on and shine it ahead, will a beam of light project forward at twice the speed of light?
Or since my flashlight and I are going forward at 186k mps, will there be no light produced by my flashlight?
My mind functions wonderfully with the "qualitative," but sucks with the "quantitative." :
Be gentle with me in your responses. "god" will bless you for your kind, tender, thoughtful responses. lol :
I wonder whether you really wanted a response!
If you stand on a train and shout, irrespective of the speed of the train, the speed of the sound will remain the same. But if you throw an apple out, the speed always depends on the speed of the train. Here the only difference is that the apple was on the train, so it took the speed of the train, while sound was not on the train. Light is similar to sound in that respect.
...of course I wanted a reply.
If I sat on the locamotive with the apple and the train was traveling at 60mph in a vacuum. If I could pitch the apple forward at 60 mph, the apple would travel at the speed of the train + the 60 mph of my pitch...or 120 mph.
If 60 mph was the fastest anything could travel and I threw the apple forward, would the apple leave my hand?
But is there any such speed limit in nature?
Is there any policeman in space, who direct the speed of 'particles'?
Sound is a wave, whose speed is dependent on the medium.
"Supposedly," nothing can travel faster than the speed of light. Doesn't that set a "limit?"
Who knows, "absolutely," the extent of limits?
Now back to my question about the apple.
Yes, supposedly! Yet light can travel faster than"c" in denser medium. Some particles called "tachyons" are supposed to travel faster than light!!
So, I think ,the speed of the apple depends on, how well you can throw it!!
in water specifically.
Variable light speed. check it out:
No, you will always measure that beam of light from your flashlight at c.
You, and your flashlight are made of mass, hence you will not attain light speeds.
OK, I am not trying to make a philosophical point about anything, I'm just asking a question (folks seem to be really touchy about that on this thread).
Isn't speed relative? I mean as I sit here on my computer I am spinning around the Earth at about 800 mph (I'm in CO), orbiting the Sun at over 30,000 mph and orbiting the galactic central point at who knows how fast but if you asked me I would say that I'm not moving at all. Because I am gauging my speed relative to the Earth.
So if you set up two flashlights in space pointing away from each other and turn them on, light will travel out of each flashlight at the speed of light. So relative to the light traveling out of the second flashlight, isn't the light coming out of the first flashlight moving at twice the speed of light?
That wasn't my question, my question is this:
Is my assumption that speed is relative true, or is there some static point in the universe that speeds are measured against?
and if there is no such static point, can this anomaly be explained by the time dilation concept some of you were talking about?
and where can I learn more about this whole time dilation idea?
OK, I guess that was three questions, sorry.
1. All observers measure the speed of light the same, no matter the reference frame (as long as there is no acceleration involved). That is one reason that Special Relativity was revolutionary.
2. Time dilation is involved, but the concept is Special Relativity.
3. Google it.
Yes, the speed of light is measured against space. It is not measured against the source of light, like the flashlights in your example, so both beams will be measured at c.
Time dilation does not refer to light, but instead the relative speeds between objects.
You can take physics courses or search online. There's plenty of information available. If you have any specific questions on what you find, just ask them here.
Well, if "light" *could* travel faster than "light," would it still *be* "light?"
There's a paradox embedded in the question itself, which should serve as a clue that it's badly posed.
But the answer is no. Light travels at the speed of light, and while it can be slowed passing through some medium, it doesn't require "acceleration" to be imposed by some external source once it emerges again into vacuum. It just travels the speed of light, even more inescapably than the way that telemarketers try to sell you stuff.
So the hypothetical black hole won't accelerate light at all, and the paradox remains purely a product of language inappropriately used.
The speed of light any time any day any where is 3*10^7(three multiply by 10 exponential seven) so i dont think force of gravity has anything to do with the speed, and by the way, scientist have been to the moon where it was reported that there is little or no force of gravity, and it wasnt reported that the little force of gravity alters the speed of light. But in your own opinion do you think the speed of light could have increase or decrease, under high gravitational force?
The short answer is no and maybe.
The 'no' is somewhat humorous, though not intended to be sarcastic. By definition, the speed of light is whatever speed light happens to travel at.
The 'maybe' is somewhat more complicated and while it has pretty solid math behind it, is still in the unproven realm of theory. Keeping it non-technical, the math seems to indicate that under certain conditions, the laws that we now observe to be the seemingly de-facto constants in the universe, can be superseded by a different set of laws. In that different set of laws, the speed of light is higher, than it is in the conditions that seem currently prevalent in our local region of the universe today. Which leads us back to the 'no' answer.
Some of the current theories revolving around the big-bang, and the idea about early universal / galactic development, try to account for exactly how things turned out as they did. Some of the math of the theories demand that certain events had to take place at a speed greater than the current speed of light in order for them to work. It is theorized that when the universe was "smaller, hotter, and denser", that a different set of laws were in operation, and that there was either no "speed of light constant" or that it was much, much faster than it is now. In those theories, as the universe cooled, the four forces of the universe (weak nuclear force, strong nuclear force, gravity, and electromagnetism), or perhaps it might be better said that the laws and conditions regarding them, 'congealed' from the original laws and conditions that prevailed prior.
In other words, even if the speed of light may have been theoretically faster in the past, the current universe is too cold to support light moving faster than it currently does.
This question is just silly. A black hole does not affect the speed light is travelling. As a matter of fact, a black hole doesn't directly affect light in any way, shape, or form. The black hole bends space, and light follows that path.
I wrote a hub on this exact topic in my early days - which was voted the rising star.
As for those saying "Nothing in the universe can travel faster than light"
You should be careful what you say. Our current understandings of physics state that light is the universal speed limit - however, this fact is in great debate...and there is a lot of work being done to change that theory. (It is just a theory, remember)
I think this is an interesting conversation but given a particular medium, the speed of light will not change, it is a constant. However, through different media the speed will change. You can do this by putting a pencil in a glass with alcohol, followed by water, followed by mineral oil. The 3 liquids have different densities and therefore will float on top of one another and alter the speed of light, thus making the pencil appear differently in each layer.
Aside from the fact that you just made 2 contradicting statements one after another - you are dead wrong.
The speed of light travels the same through these things. The densities have nothing to do with how fast light travels. Also...if the speed of light did change...it would not change the appearance of the pencil whatsoever...you would simply see some parts of the pencil before other parts (assuming the change was drastic enough).
The change in appearance you speak of is a change in the *dispersion* of light particles...which has absolutely nothing to do with the speed.
Light travels at different speeds depending on what kind of light it is.
The fastest I've seen is"Bud Light"...cause a six pack disappears in plank time.
An addendum, based on some comments I've seen indicating that the speed of light cannot change.
In fact, the speed light travels at varies all the time. The theoretical maximum speed, is the "speed of light" that most people are talking about, is the unimpeded speed light travels at in a perfect vacuum.
However, when traveling through a medium denser than a perfect vacuum, the speed light travels at actually is slower than that maximum. Everyone living on earth who can see has already observed this. As light passes through an atmosphere, through water, even through clouds of gas in space, light can travel at a speed slower than the maximum stated as the "constant".
Here's how that works. Photons come in contact with a particle in the medium, which absorbs the photon thus increasing the particles energy. The particle, going back to it's ground state, emits the photon.
Between particles, light is still traveling at c. It is the extra time required for absorptions and emission of the photon that changes the overall speed through that medium and makes it appear as if the light has indeed slowed.
I'm by no means an expert on this topic, but from my constantly devouring of every astronomy documentary I can get my hands on -- especially anything featuring Dr. Michio Kaku -- it was my understanding that the early expansion of the universe was not, in fact, moving faster than light, because that implies an object moving through the fabric of space, whereas what was actually happening is that the fabric of space was expanding at a rate that we would think of as faster than light.
I'm not sure I explained that very well. In other words, that expansion wasn't particles within our universe traversing space; rather, space itself was stretching. Which is a different set of laws of physics entirely, since that's space moving through whatever matrix is outside our universe.
I find all this string theory stuff -- and black holes! -- fascinating.
By the way, not only is the universe expanding, but it is expanding at an ever increasing rate. Which fact has now seemingly debunked the old companion theory to the Big Bang, that of the Big Crunch.
What you are referring to is called inflation. These fields are my #1 hobby ;-)
According to Einstein's special theory of relativity, light traveling in a vacuum is the universal speed limit. But scientists love to try and break rules and now a tweaked version of Einstein's equations suggests that faster-than-light travel might just be possible.
In other words, the theory isn't suddenly going to see a host of Earth-bound experiments revealing particles that zip through the air faster than light, nor will it produce a warp drive (at any rate, NASA is already working on that).
A beam of light and a black hole walk into a bar... the bartender asks them what they'll have. The beam says he'll have a Bud, the black hole says he'll have a light. The beam looks at him in disgust and says, "Don't you think you've had enough!"
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