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Incognitum: It looks like you should read some books on relativity

Perhaps my posts have been too technical for you to follow, but I would submit that my library has a sufficiently large section devoted to relativity and related concepts.

Please have the courtesy in future to cite specific objections that may be rebutted or revised; this nebulous disparaging of my literacy is not appreciated.

Make no mistake, if you think I have erred I welcome you to bring it to my attention, but please help me mend my erroneous notions by demonstrating the fallacy in question.

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Please have the courtesy in future to cite specific objections that may be rebutted or revised; this nebulous disparaging of my literacy is not appreciated.

Incognitum,

Sorry for the lack of courtesy in not citing the specific objection. It was, however ment to be vague. I was simply throwing back the same comment you made to Cipher22. It appeared that you were arogantly tearing down (instead of building up by the strength of your own arguments) when you stated that Cipher22 should read a book or two before posting again.

The specific objection was relating to your brick analogy, which you responded to Headswabby and dug yourself an even deeper hole. What you are saying about the the speed of light is correct and I think everyone understands what you meant by the maximum "weight" of a brick, it is simply not stated correctly. The weight of the same brick can change. Theoretically there is no maximum, practically there is sure to be. But the fact that a bricks weight can change and the speed of light does not makes it a poor analogy (in my opinion). Maybe I have misunderstood your response to Headswabby, but from my point of view you were grasping at straws. Maybe you can explain it to me in a way that is not too technical for me to follow.

I accept your proposition that your library has a sufficiently large section devoted to relativity and related concepts. However, because you have them does not mean that you read them. So what does the size of your library have to do with anything?

P.S. Don't take anything I am writing too seriously, bleive me, I don't. I am just having a little fun. I could'nt have hard feeling towards a Feynman fan.

Could you do me a favor? Can you please provide an explanation for your signature:

Poinete! Ede, ede; tachu, tachu!

Thanks

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First, this is wrong. The MAXIMUM weight of a brick is a constant, regardless of specific gravity, density of atmosphere, variabilities in brick manufacture etc... The MAXIMUM amount will be the one where all these variables are at the position on the spectrum which results in greatest measure of weight. This is what MAXIMUM means. Therefore, it is a perfect analogy to the speed of light, which also is a constant.

Weight implies the amount of gravitational force on an object is being taken into account.

Second, no, this is wrong. You will not think your headlights are broken because relative to your position in the car your headlights will travel away from you at the speed of light. Celeritus ('C') is constant relative to ALL observers; including you in the car.

Sorry, I should have been more more specific. I'll agree I was not very exact about my statements. What I meant to state was that to an outside observer, the headlights would appear broken. The headlights to the driver would be fine and operating properly.

Third, Being as no time machine has ever been invented, how do you know the operating principle used in it's design? ...Unless you have a time machine and went to the future to ask...

No. I don't have a time machine. Yes I have had physics talks describing what must occur for a time machine to be possible. Let me explain my statement. The twins paradox shows that traveling near the speed of light results in one twin aging slower than the other. If we take this example and extrapolate to the speed of light, time should theoretically stop, and therefore if it were possible to travel faster than the speed of light, you would theoretically be going in reverse time.

Now I may be flawed in my thinking, but this would be the most obvious way to time travel instead of creating alternate whatevers and time skipping through coincidence.

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1. Let's say (hypothetically) there is a bullet, which can shoot through any barrier. Let's say there is also an absolutely bullet-proof armour, and nothing gets through it. What will happen, if such bullet hits such armour?

This is the same as what happens if an unstoabble force meets an immovable object. This is the subjct of a long debate so I say:

who cares? neither exist.

2. Can a man drown in the fountain of eternal life?

Yes - but they wouldn't die

besides don't you have to drink from it?

3. Your mission is to not accept the mission. Do you accept?

yes I do. once I accept however if you ask me again I refuse.

4. This girl goes into the past and kills her Grandmother. Since her Grandmother is dead the girl was never born, if she was never born she never killed her grandmother and she was born.

This is the grandfather paradox and the answer depends on whether the past is state based to fact based and a bunch of other debates.

5. If the temperature this morning is 0 degrees and the Weather Channel says, "it will be twice as cold tomorrow,".... What will the temperature be?

zero degrees

2 * 0 = 0

it is the same as asking "what number is twice itself?"

6. Answer truthfully (yes or no) to the following question: Will the next word you say be no?

you can answer yes or no. if you say yes then you say "yes no" and if you answer no you say "no blah"

7. What happens if you are in a car going the speed of light and you turn your headlights on?

ha ha - you can't go the speed of light anyway.

8. I conclude with this challenge:

Let the God Almighty create a stone, which he can not pick up (is not capable of lifting)!

To answer this without saying my religion. I make no comment as to what I beleave.

God can not do everything. God is not perfect. God is no word that describe him. He can not be understood by humans. He is 'limited' by his perfection and as such can not do something that would later imped his ability. Therefore god can not create another god or anything like that.

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correct me if i'm wrong but an unstoppable force can be created:

imagine a wire one atom thick: it would have an (near) infinite pressure and so by adding just a tiny amount of force would cut through anything (because Pressure=Force/Area so if area=0 (or as close as you can get) then any force creates infinite pressure.) on the other hand, it is impossible to make an object which could stop this from slicing through.

and in answer to 8, it is really very simple: God does not exist ....problem solved...

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Incognitum,

Sorry for the lack of courtesy in not citing the specific objection. It was, however ment to be vague. I was simply throwing back the same comment you made to Cipher22. It appeared that you were arogantly tearing down (instead of building up by the strength of your own arguments) when you stated that Cipher22 should read a book or two before posting again.

I would make three points about this:

First, that Cipher22's comments were demonstrably wrong, and I explained in detail how before disparaging them.

Second, that Cipher22 was purporting to bring to the table ideas that were brought second-hand from his chem teacher, and not concepts that he had personal knowledge of. I was very upset by the report of a public school teacher giving such hogwash to his students, and my remark was meant to be a directive to seek knowledge from a better source, although I admit it was phrased rather harshly.

Third, that Cipher22 had intentionally crafted his post to be inflammatory towards those who understand the concepts being discussed, in the hopes of baiting a response such as was furnished.

The specific objection was relating to your brick analogy, which you responded to Headswabby and dug yourself an even deeper hole. What you are saying about the the speed of light is correct and I think everyone understands what you meant by the maximum "weight" of a brick, it is simply not stated correctly. The weight of the same brick can change. Theoretically there is no maximum, practically there is sure to be. But the fact that a bricks weight can change and the speed of light does not makes it a poor analogy (in my opinion). Maybe I have misunderstood your response to Headswabby, but from my point of view you were grasping at straws. Maybe you can explain it to me in a way that is not too technical for me to follow.

I don't know how to explain any simpler then I did in my last post. The maximum weight of a brick cannot change. The idea that whatever brick you make, someone can always make a heavier one, or put it in a stronger gravity well is irrelevant. The maximum weight will be where all the variables for gravity, size, materials, and any other pertinent considerations are all set so that the maximum weight is achieved. Even if this means the maximum weight of a brick is one atom away from it collapsing on itself and becoming a black hole, whatever the limit, that limit is not maileable. That is why it is the maximum.

I am quite unsure however, how this off-hand comment became such a big part of the discussion. The part of the example that was pertinent was the answer.

P.S. Don't take anything I am writing too seriously, bleive me, I don't. I am just having a little fun. I could'nt have hard feeling towards a Feynman fan.

No harm done, I was just very surprised as I know my physics are sound (even if there is disagreement about my metaphors) and I wanted to know what you objected to so I could riposte appropriately. Knowing that you impugn only my knowledge of astro-masonry, and not that of special relativity, I am quite content.

Could you do me a favor? Can you please provide an explanation for your signature:

Thanks

No trouble, it's Greek. Translated it means, "Do it! Now, now; quick, quick!" It is from an ancient Greek love spell that my brother found while doing research for his master's thesis. This spell is purported to cause "men to fall in love with women, women to fall in live with men, and virgins to run out of their houses."

First you draw a demon on parchment. This demon is headless, and his name is a synonym for 'envy.' Then you tack this image up over the door to the public bathhouse and recite the magic words. Then! ...you wait.

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correct me if i'm wrong but an unstoppable force can be created:

imagine a wire one atom thick: it would have an (near) infinite pressure and so by adding just a tiny amount of force would cut through anything (because Pressure=Force/Area so if area=0 (or as close as you can get) then any force creates infinite pressure.) on the other hand, it is impossible to make an object which could stop this from slicing through.

and in answer to 8, it is really very simple: God does not exist ....problem solved...

yes... and again in theory, could not all space be removed from between the atoms of a given surface, creating an armor through which nothing could pass?

if so, then when the bullet struck the armor, would it not actually be simply a collision of two atoms (the foremost on the bullet, and whichever atom said atom struck upon the armor)? and so my guess is that the answer to "what would happen" is fusion... and a subsequent nuclear explosion.

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yes... and again in theory, could not all space be removed from between the atoms of a given surface, creating an armor through which nothing could pass?

No. Atoms are mostly empty space themselves. Even if they were lined up next to each other and glued in place, most of your armour would be empty space. It is only the dense nucleus that reflect alpha particles. But it will be seen that since scientists can split these nuclei, I would submit that no armour is impenetrable to atomic bombardment.

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No. Atoms are mostly empty space themselves. Even if they were lined up next to each other and glued in place, most of your armour would be empty space. It is only the dense nucleus that reflect alpha particles. But it will be seen that since scientists can split these nuclei, I would submit that no armour is impenetrable to atomic bombardment.

i readily defer to your better informed judgment on all things atomic... assuming it were possible to extract the nuclei (thereby removing the space) and fashion an armor thereof... is not atomic bombardment the very process by which fusion is begotten? would that not be the very end result i have proposed? (doesn't seem all that much less likely than a bullet honed to an single-atom tip to me, at any rate)

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No. Atoms are mostly empty space themselves. Even if they were lined up next to each other and glued in place, most of your armour would be empty space. It is only the dense nucleus that reflect alpha particles. But it will be seen that since scientists can split these nuclei, I would submit that no armour is impenetrable to atomic bombardment.

i readily defer to your better informed judgment on all things atomic... assuming it were possible to extract the nuclei (thereby removing the space) and fashion an armor thereof... is not atomic bombardment the very process by which fusion is begotten? would that not be the very end result i have proposed? (doesn't seem all that much less likely than a bullet honed to an single-atom tip to me, at any rate)

Sort of, certainly it is not the case that a particle accelerator is synonyms with a nuclear reactor. Not every material can be used in an atomic bomb, but any atom can be split into quarks. Assuming you aren't making this armour out of uranium-32 it should be plenty safe to split.

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As to the one about a car going the speed of light and turning the headlights on. You could relatively compare it to someone going the speed of sound and turning on music. The driver still hears the music therefore I believe the driver would still see his headlights (inertia). Any effect on a bystander would be mere speculation due to the fact that no man made object has reached the speed of light yet. My best guess would be that a bystander would see nothing but a flash and that there would be some sort of after effect like a sonic boom when the sound barrier is broken.

Another question you could ask is when a car is going 55 mph and turns on the headlights, is the light now traveling the speed of light plus 55 miles per hour?

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#7:

This is a problem that is inspired by relativity. As I understand it, this is what would happen:

First, the car cannot go the speed of light. Accellerating it to the speed of light would require an infinite amount of energy because, in relativity, momentum is conserved, so the mass is forced to increase as the velocity approaches c. It is an unreachable limit, and reaching it would entail instantaneous travel, surpassing it would allow for travel backwards through time, reaching a result event before the cause.

If it were possible, my guess is that an observer in a car travelling the speed of light would be frozen in time and would not witness anything at all.

If the car was travelling arbitrarily CLOSE to the speed of light, things from the driver's point of view would be normal, and he would see the light travel away from him at the speed of light (the speed of light is the same for all observers, no matter how fast they are going). An outside observer (assuming he could keep track of what's going on), would see slow motion people in the car and the light from the headlights slowly outpacing the car.

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For number 5, you convert to Fahrenheit.

Soo... 0 degrees Celsius is 32 degrees Fahrenheit.

1/2 of 32 = 16

16 degrees Fahrenheit = approximately -8.6 degrees Celsius.

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Another question you could ask is when a car is going 55 mph and turns on the headlights, is the light now traveling the speed of light plus 55 miles per hour?

There is no speed for C+55m/h. C can be slowed by an impediment such as air, glass, or gravity, but no force in the universe can make it go faster (according to relativity, QED produces some interesting results that suggest otherwise, but only in certain specially defined circumstances)

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For number 5, you convert to Fahrenheit.

Soo... 0 degrees Celsius is 32 degrees Fahrenheit.

1/2 of 32 = 16

16 degrees Fahrenheit = approximately -8.6 degrees Celsius.

Nope, that won't work. As I stated earlier:

#5 is a problem with unrigorous language. There is no measure of 'twice as cold' We measure the warmth of things, not their coldness. Just as there is no twice as thin, or three times less wealthy. Where does the thinness scale start? at 300 lb? 800lb? With no concrete and finite starting place for the scale, the increments are indefinable, and multiplication cannot occur.

Switching from Fahrenheit to kelvin solves nothing, because there is a Fahrenheit equivalent for any temperature. The question is where and when is he measuring the first drop to 0, that he can double that drop again tomorrow. Is it twice as cold as yesterday? As 6 months ago? as ten minutes ago? The scale is not defined. It's not a conversion problem. Even if you did transfer to Kelvin and subtract half, you'd be subtracting a nominal amount only since the increments are of different size. It would be a meaningless exercise.

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Cipher22: you capitulated too quickly.

Are you kidding? I'm 16. Is that actually one of the theories? Besides, nobody knows for sure just what will happen at that speed, even if your spaceship is inside a 'bubble' of antigravity, which we aren't even sure exists....of course, there is the cashmir effect (probably spelled that wrong) but that's not really antigravity.

@Kingmadmushroom: lol You beat me to it. The simple Atheist answer.

Actually I don't really believe God is almighty in the sense that he can intervene in person at any time and fix whatever he wants to. Otherwise we might have world peace, clean energy, and a chicken in every pot. I think he built the world more like a mechanical watch that just needs to be wound up again every now and then. He could still beat me up on the playground after school though.

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# This girl goes into the past and kills her Grandmother. Since her Grandmother is dead the girl was never born, if she was never born she never killed her grandmother and she was born.

I always had this problem with Back to the Future.

If he kept his parents from getting together, then he disappeared...but since he was not born, he didnt screw with their meeting...etc etc etfc..

That would probably be the point at which time ripped apart

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i would just like to point out (and correct me if im wrong) that it is first of all impossible to go the speed of light. i know this has been previously mentioned but i felt like reiterating the fact. and also that the speed of light is the fastest you can go. you cant go faster then the speed of light because light has no mass and therefore is going the fastest as is possible. so therefore when you turn on the headlights while going the speed of light, which is impossible anyways, the light would not shoot out ahead of you it would simply keep pace with you. i anxiously await your rebuttal

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i would just like to point out (and correct me if im wrong) that it is first of all impossible to go the speed of light. i know this has been previously mentioned but i felt like reiterating the fact. and also that the speed of light is the fastest you can go. you cant go faster then the speed of light because light has no mass and therefore is going the fastest as is possible. so therefore when you turn on the headlights while going the speed of light, which is impossible anyways, the light would not shoot out ahead of you it would simply keep pace with you. i anxiously await your rebuttal

You're wrong, that was me correcting you.

The first thing I need to point out is that there are several unique circumstances under which things (information, particles, and light) can travel faster then light, or, perhaps if we're not quite right about things, then at least they seem to. However, at at deeper level, apparently you don't quite grasp what the 'relativity' part of general relativity is all about.

When you state that it is impossible to travel at the speed of light, how do you know if you have? You presumably measure by traveling to a star, but how do you know the star isn't moving? In fact, Hubble's law states that every star in the sky has a recessional velocity. So when you reach your star and check your watch, do you know that you were moving that fast, or might the star have been moving at a rate unequal to that which you thought?

Imagine you are driving in your car at what you think is 55km/h. Now if we want to know how fast you are actually moving we need to know if you are driving east or west, because the earth rotates at a speed of about 1,609km/h which must be accounted for, so your speed is actually 55+/-1,609km/h. But wait, there's more! Now you must ask whether it is day or night, because the earth is flying around the sun at a rate of about 108,000km/h. So your actual speed is 55km/h +/- 1,609km/h +/- 108,000km/h. But we're not done yet, because our solar system is swinging around the galactic center, and our galaxy is speeding away from the point of the big bang. And we cannot discount the possibility of motions other then this we have no way to measure. This is the heart of relativity; there is no fixed place to measure from, so the only metric that has any use is the relative speed between two objects (like your car and the road), not the absolute speed, which is impossible to know, and difficult to guess at.

The speed of light is a constant (in vacuum) relative to all observers. Therefore, if traveling at the speed of light in your car, you and your headlights are at rest *relative to each other*. This means that when you turn your headlights on, the light must shoot out from your car at the speed of light *relative to you*. It is true that to an independent observer not traveling with you, the headlights would seem NOT to emit from the car, because relative to them you are both traveling at an equal rate.

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i completely understand your points and i see the reason in them. i'll also admit yes i have not studied physics and the theories that go along with physics that much, and not nearly as much as you have obviously. but thinking logically and scientifically, the thought that you can go faster then the point at which you have no mass.....it just doesnt make much sense to me. but it only doesnt make sense when i follow the mindset that everything has set rules and there are no outliers. the way you describe the headlights coming out and appearing differently to two different observers completely defies logic and makes it seem to me that rules can be bent, molded to fit the situation so to speak. which is the way i prefer to look at things. but im not sure how radical that train of thought is and how many people would understand/agree with that way of thinking. unless im just completely misunderstanding what you're saying.

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i completely understand your points and i see the reason in them. i'll also admit yes i have not studied physics and the theories that go along with physics that much, and not nearly as much as you have obviously. but thinking logically and scientifically, the thought that you can go faster then the point at which you have no mass.....it just doesnt make much sense to me. but it only doesnt make sense when i follow the mindset that everything has set rules and there are no outliers. the way you describe the headlights coming out and appearing differently to two different observers completely defies logic and makes it seem to me that rules can be bent, molded to fit the situation so to speak. which is the way i prefer to look at things. but im not sure how radical that train of thought is and how many people would understand/agree with that way of thinking. unless im just completely misunderstanding what you're saying.

I am confused by the way you keep referring to the speed of light as the point at which you have no mass.... As you approach the speed of light your mass increases, it doesn't decrease. And I don't suggest that you or I can go faster then light. It is completely true that we have seen particles pop into being out of nothingness, and then travel back in time to animate themselves before they do. This doesn't mean I am advocating a workable system of either defying the law of Conservation of Mass, or that it is feasible to time travel in anything like a commercial scale. These are laboratory tricks only, but they do prove that the 'absolutes' about our universe do not always hold true. Or to be more precise, that the 'absolutes' which always hold true aren't always the ones we think they are going to be.

On a side note, if you are interested in reading up on these things, I cannot recommend highly enough 'A Short History of Nearly Everything' by Bill Bryson. It is plenty accessible for the general reader, and is I think the most informative book I have ever read, textbooks included. A little more technical, but an excellent reference book is "who's Afraid of Schrudinger's Cat', unfortunately I just moved and not all my books are to hand at the moment so I can't give you the author, also my copy is about 10 years old, so if there's no new addition it may be a little out of date, but a worthy read nonetheless. The book that got me started on this line of inquiry in the first place, 'The Physics of Star Trek' is quite an interesting read; although somewhat shallow on the physics, it is good for stirring an inquiring mind. Any of the Feynman books have great nuggets of physics in them, as well as the zany and enchanting real life antics of Nobel laurite physicist Richard P. Feynman. Although it must be said, most of this physics will be QED and not relativity. A friend of mine who is actually a physicist recommended I read ‘The Fabric of the Cosmos,’ but alas, I have not yet done.

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i might check into that. i say that the speed of light has no mass because i heard that from someone else, i guess he was wrong.but when you say that there are exceptions to absolutes, that confuses me. the very definition of an absolute is that it IS absolute and there are no exceptions. so if what you say about there being exceptions to certain absolutes then it would occur to me that they really arnt the absolutes we think they are, and might need to be refined somewhat. and let me say that if im alot more ignorant then i think i am i realize how frustrating a conversation with me might be and so if that is happening just say so and i'll understand

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