Strange Posted October 31, 2018 Posted October 31, 2018 2 minutes ago, Menan said: Was there a way to the moon before the way was created? I don't know what that means. People had imagined flying to the moon for millennia before we actually did it. Asking if something exists before it is created sounds like a year 1 philosophy debate. 3 minutes ago, Menan said: Again creation is not an option, we create a way off, or die here. (adapted from Hawking) Maybe we never get to explore space apart from the nearby planets. Who knows. But in my lifetime, I will have to stick to SF to enjoy space travel!
koti Posted October 31, 2018 Posted October 31, 2018 2 minutes ago, Strange said: But in my lifetime, I will have to stick to SF to enjoy space travel! Ah but there is medicine, Elon Musk and the lottery so don’t be so sure
Strange Posted October 31, 2018 Posted October 31, 2018 Just now, koti said: Ah but there is medicine, Elon Musk and the lottery so don’t be so sure I could start buying lottery tickets to get into space. It might work. But it would still only be low-earth orbit or, maybe, a one way trip to Mars. No one is going outside the solar system or to another star any time soon.
koti Posted October 31, 2018 Posted October 31, 2018 Just now, Strange said: I could start buying lottery tickets to get into space. It might work. But it would still only be low-earth orbit or, maybe, a one way trip to Mars. No one is going outside the solar system or to another star any time soon. Think about what your life would look like if you were born in the 13th century, that should cheer you up.
Strange Posted October 31, 2018 Posted October 31, 2018 3 minutes ago, koti said: Think about what your life would look like if you were born in the 13th century, that should cheer you up. Or even the 19th, to be honest.
koti Posted October 31, 2018 Posted October 31, 2018 3 minutes ago, Strange said: Or even the 19th, to be honest. Nah, the 19th century was a wonderful time to be alive in in my opinion, just look at all the dicoveries in physics that were made. Ofcourse its all relative but if were to chose between 13th and 19th century the choice would be easy for me.
Strange Posted October 31, 2018 Posted October 31, 2018 15 minutes ago, koti said: Nah, the 19th century was a wonderful time to be alive in in my opinion, just look at all the dicoveries in physics that were made. Ofcourse its all relative but if were to chose between 13th and 19th century the choice would be easy for me. True. But unless you were wealthy and healthy neither would be great! (Although the same could be said now...) 2
Janus Posted October 31, 2018 Posted October 31, 2018 4 hours ago, Menan said: Was there a way to the moon before the way was created? Again creation is not an option, we create a way off, or die here. (adapted from Hawking) Traveling to the Moon was a matter of solving known engineering problems, it was not considered theoretically impossible. Exceeding c is an entirely different animal. It is a fundamental limit built into nature itself. You bring up the matter of "weight". But weight is not the issue. "Inertia" or the resistance to further change in velocity is a better way to look at it. It takes energy to overcome inertia. This was known even before Relativity came on the scene. In Newtonian physics, it takes 1/2 joule of energy to acceleration a 1 kg mass from 0 to 1m/sec. The amount of energy needed to any given speed is found by E= mv2/2 The kicker added by Relativity is that energy itself carries inertia. So when you add energy to the 1 kg mass to accelerate it up to 1/m per sec, you are also adding to its inertia. When you try to accelerate it further, you have to supply more energy than you would have without the added inertia. But this extra added energy increases the inertia even more. The amount of energy rises a lot faster than it does under Newtonian physics. The equation that give the amount of energy is E = mc2(1/sqrt(1-v2/c2)-1) The amount of energy heads off to infinity as v approaches c. The flip side of this is that no matter how much energy you add, you always end up moving less than the speed of light. This is not to say that the speed of light limit is all about energy. This is just one consequence. It goes deeper than that. It actually delves to the very nature of space and time itself. Another consequence of this is how we add velocities together. Again, under Newton, it is quite simple. we just add them directly. So, for example if you are on a railway car traveling at 60 mph, and you walk from the back to the front at 5 mph relative to the car, According to Newton, you would be moving at 60+5= 65 mph relative to the tracks. But in Relativity, with its altered nature of time and space, you have to use the formula: (5+60)/(1+5(60)/c2) = ? Now c = 186,000mps = 669,600,000 mph, so if you do the math you will get an answer really, really close to 65 mph, but just a tad less. The difference becomes more apparent as the velocities added up get closer to the speed of light. This also applies when you are adding up velocities for an accelerating object. In Newtonian physics you could have an object that accelerate up to 0.1c, and then accelerate another 0.1c, and then another, etc so that after each stage, its velocity would look like this: 0 0.1c 0.2c 0.3c 0.4c And after ten of these you would reach c However, with Relativity, the velocity doesn't add up like that. You can accelerate up to 0.1c, and then accelerate (as measured by you) another 0.1c, but will end up moving at only 0.198c relative to where you started. You can then accelerate by another 0.1c, and another, etc. Your pattern of resulting velocities will be: After 10 such accelerations, you have only reached a little over 3/4 the speed of light. Also note that each successive acceleration results in a smaller and smaller change of velocity. The increase in velocity shrinks at a rate such that no matter how many times you try to add speed(or by how much), you always end up with a velocity less than the speed of light relative to where you started. 3
Olin Posted October 31, 2018 Posted October 31, 2018 (edited) 7 hours ago, Strange said: I don't know what that means. People had imagined flying to the moon for millennia before we actually did it. Asking if something exists before it is created sounds like a year 1 philosophy debate. Maybe we never get to explore space apart from the nearby planets. Who knows. But in my lifetime, I will have to stick to SF to enjoy space travel! How did people imagine flyingto the moon millennia ago when the moon and stars were not even known to be places that could be traveled to? They were painted on the sky for all anyone knew 9 hours ago, Strange said: It was a joke made 100 years ago. It wasn’t true then and certainly isn’t true now. It is taught in every university. It is used in many areas of science and technology. What!? It is constantly being studied and developed. One of the challenges is understanding more complex situations where GR applies. There are only analytical solutions for a few simple cases like symmetrical spheres in an empty universe (which is a good enough approximation for many real world applications). Another area of work is understanding the relationship between GR and quantum theory. There has been (and continues to be) a lot of new ideas coming from that - from Hawking radiation to ideas to explain dark matter or dark energy. It is relativity (and evidence) that tells us that 85% is unknown! LRelativistic mass is just a measure of increased energy (mass and energy are related, remember: e=mc2). A lot of people say the concept should not be used because it causes too much confusion (as in your question). Where do you find an empty universe to even put a symmetrical sphere? Is this universe empty? You can do this forever and never really makesense 1 hour ago, Janus said: Traveling to the Moon was a matter of solving known engineering problems, it was not considered theoretically impossible. Exceeding c is an entirely different animal. It is a fundamental limit built into nature itself. You bring up the matter of "weight". But weight is not the issue. "Inertia" or the resistance to further change in velocity is a better way to look at it. It takes energy to overcome inertia. This was known even before Relativity came on the scene. In Newtonian physics, it takes 1/2 joule of energy to acceleration a 1 kg mass from 0 to 1m/sec. The amount of energy needed to any given speed is found by E= mv2/2 The kicker added by Relativity is that energy itself carries inertia. So when you add energy to the 1 kg mass to accelerate it up to 1/m per sec, you are also adding to its inertia. When you try to accelerate it further, you have to supply more energy than you would have without the added inertia. But this extra added energy increases the inertia even more. The amount of energy rises a lot faster than it does under Newtonian physics. The equation that give the amount of energy is E = mc2(1/sqrt(1-v2/c2)-1) The amount of energy heads off to infinity as v approaches c. The flip side of this is that no matter how much energy you add, you always end up moving less than the speed of light. This is not to say that the speed of light limit is all about energy. This is just one consequence. It goes deeper than that. It actually delves to the very nature of space and time itself. Another consequence of this is how we add velocities together. Again, under Newton, it is quite simple. we just add them directly. So, for example if you are on a railway car traveling at 60 mph, and you walk from the back to the front at 5 mph relative to the car, According to Newton, you would be moving at 60+5= 65 mph relative to the tracks. But in Relativity, with its altered nature of time and space, you have to use the formula: (5+60)/(1+5(60)/c2) = ? Now c = 186,000mps = 669,600,000 mph, so if you do the math you will get an answer really, really close to 65 mph, but just a tad less. The difference becomes more apparent as the velocities added up get closer to the speed of light. This also applies when you are adding up velocities for an accelerating object. In Newtonian physics you could have an object that accelerate up to 0.1c, and then accelerate another 0.1c, and then another, etc so that after each stage, its velocity would look like this: 0 0.1c 0.2c 0.3c 0.4c And after ten of these you would reach c However, with Relativity, the velocity doesn't add up like that. You can accelerate up to 0.1c, and then accelerate (as measured by you) another 0.1c, but will end up moving at only 0.198c relative to where you started. You can then accelerate by another 0.1c, and another, etc. Your pattern of resulting velocities will be: After 10 such accelerations, you have only reached a little over 3/4 the speed of light. Also note that each successive acceleration results in a smaller and smaller change of velocity. The increase in velocity shrinks at a rate such that no matter how many times you try to add speed(or by how much), you always end up with a velocity less than the speed of light relative to where you started. Einstein was a negative pessimist, which is why with all his ability he never created built or patented anything. His world knew hunger but all he ever did was to remain in school as a perpetual child who was too simple to comb his hair. Would you be reading this now if everyone agreed it couldn't be done? Your problem is you are listening to the imbecile who said that the universe was a bubble.... Term bubblebrain Edited October 31, 2018 by Olin -3
Strange Posted October 31, 2018 Posted October 31, 2018 1 hour ago, Olin said: How did people imagine flyingto the moon millennia ago when the moon and stars were not even known to be places that could be traveled to? They were painted on the sky for all anyone knew People are fantastically imaginative. And there are good reasons for thinking the moon is spherical (the phases, for example). So examples of early moon landings here: https://en.wikipedia.org/wiki/Moon_landings_in_fiction 1 hour ago, Olin said: Where do you find an empty universe to even put a symmetrical sphere? Is this universe empty? You can do this forever and never really makesense The trouble is that the Einstein Field Equations are complex and non-linear. So the known solutions involve very simplified cases. A Schwarzschild black hole (perhaps one of the most commonly used solutions) assumes an eternal, unchanging spherical mass in an empty universe. Given how far apart things are in the real universe, this is still a good approximation. More complex situations, such as a pair of orbiting black holes, require massive simulations to find out what happens. 1 hour ago, Olin said: Einstein was a negative pessimist, which is why with all his ability he never created built or patented anything. Actually, he patented a refrigerator: https://en.wikipedia.org/wiki/Einstein_refrigerator 1 hour ago, Olin said: Would you be reading this now if everyone agreed it couldn't be done? Janus is describing the effects of special relativity. If it weren't for special relativity, and therefore quantum field theory, you wouldn't have the computer you are positing this on. 2
Olin Posted October 31, 2018 Posted October 31, 2018 46 minutes ago, Strange said: People are fantastically imaginative. And there are good reasons for thinking the moon is spherical (the phases, for example). So examples of early moon landings here: https://en.wikipedia.org/wiki/Moon_landings_in_fiction The trouble is that the Einstein Field Equations are complex and non-linear. So the known solutions involve very simplified cases. A Schwarzschild black hole (perhaps one of the most commonly used solutions) assumes an eternal, unchanging spherical mass in an empty universe. Given how far apart things are in the real universe, this is still a good approximation. More complex situations, such as a pair of orbiting black holes, require massive simulations to find out what happens. Actually, he patented a refrigerator: https://en.wikipedia.org/wiki/Einstein_refrigerator Janus is describing the effects of special relativity. If it weren't for special relativity, and therefore quantum field theory, you wouldn't have the computer you are positing this on. That's nonsense, computers are directly traced back to vacume tube transistors. Really. There is nothing scy fi about programming either. 53 minutes ago, Strange said: People are fantastically imaginative. And there are good reasons for thinking the moon is spherical (the phases, for example). So examples of early moon landings here: https://en.wikipedia.org/wiki/Moon_landings_in_fiction The trouble is that the Einstein Field Equations are complex and non-linear. So the known solutions involve very simplified cases. A Schwarzschild black hole (perhaps one of the most commonly used solutions) assumes an eternal, unchanging spherical mass in an empty universe. Given how far apart things are in the real universe, this is still a good approximation. More complex situations, such as a pair of orbiting black holes, require massive simulations to find out what happens. Actually, he patented a refrigerator: https://en.wikipedia.org/wiki/Einstein_refrigerator Janus is describing the effects of special relativity. If it weren't for special relativity, and therefore quantum field theory, you wouldn't have the computer you are positing this on. If you read your own link it says that Einstein filed the patents and the other collaborator was the actual inventor
Strange Posted October 31, 2018 Posted October 31, 2018 49 minutes ago, Olin said: That's nonsense, computers are directly traced back to vacume tube transistors. I know that. But I also know that transistors were developed based on quantum theory. 51 minutes ago, Olin said: If you read your own link it says that Einstein filed the patents and the other collaborator was the actual inventor "It has been suggested that most of the actual inventing was performed by Szilárd, with Einstein merely acting as a consultant and helping with the patent-related paperwork,[1] but others assert Einstein labored over the project.[2]"
Menan Posted October 31, 2018 Posted October 31, 2018 11 minutes ago, Strange said: I know that. But I also know that transistors were developed based on quantum theory. "It has been suggested that most of the actual inventing was performed by Szilárd, with Einstein merely acting as a consultant and helping with the patent-related paperwork,[1] but others assert Einstein labored over the project.[2]" You have a great imagination, but just haven't been correct yet http://www.sjsu.edu/faculty/watkins/transist.htm Shockley had started working in 1936 on the solid state physics theory that was the basis for the transistor. There was precedence for this type of device. The early radios had signal detectors which consisted of a fine wire, called a cat's whisker, impinging upon a galena (lead sulfide) crystal. The radio user had to move the cat's whisker around upon the germanium crystal to find a suitable point of contact where a radio signal could be picked up. These early radios worked but only imperfectly. Nevertheless the principle upon which the crystal detector worked was the basis for the "point-contact" transistor. Bardeen and Brattain used germanium instead of galena in that first transistor. They also used the equivalent of cat's whiskers, but two rather than one. Shockley's design, the bipolar transistor, eliminated the delicate, troublesome point contacts. Later transistors were made from silicon, a much more common element and one that was protected from corrosion by a thin layer of silicon dioxide.
Strange Posted October 31, 2018 Posted October 31, 2018 35 minutes ago, Menan said: Shockley had started working in 1936 on the solid state physics theory that was the basis for the transistor. There you go. That "solid state physics theory" is the (quantum) physics of semiconductors. A bit more detail here: https://web.stanford.edu/dept/HPS/TimLenoir/SiliconValley99/Transistor/RiordanHoddeson_Inventtransistor.pdf
Menan Posted November 1, 2018 Posted November 1, 2018 13 hours ago, Strange said: There you go. That "solid state physics theory" is the (quantum) physics of semiconductors. A bit more detail here: https://web.stanford.edu/dept/HPS/TimLenoir/SiliconValley99/Transistor/RiordanHoddeson_Inventtransistor.pdf Zero theory was used in building the CPU. Modern CPU's are the result of continued trial and error experimentation. Your mind relates everything to relativity, including the Reese's Pieces that you eat for breakfast. -2
Strange Posted November 1, 2018 Posted November 1, 2018 39 minutes ago, Menan said: Zero theory was used in building the CPU. Modern CPU's are the result of continued trial and error experimentation. As I have spent a large part of my career designing CPUs I know this not true. But you carry on with your irrational beliefs.
jajrussel Posted November 1, 2018 Posted November 1, 2018 On 10/3/2018 at 11:27 AM, snick said: Hey guys, this may sound stupid but I am quite new to theoretical physics and I want to learn more. So, my question is, do objects move faster when you move towards them, for example at the speed of light? If you, for instance, move towards Andromeda at the speed of light, which is around 2.5 million light years away from us, for 100 years(just theoretically), Andromeda will be 2 499 900 light years away from us. That means the light from Andromeda will reach you faster than at the Earth. Does not that mean that while moving it should be rotating faster from your perspective, for example? The whole Primus is that regardless how fast you are moving you will always measure the speed of light in a vacuum as c. Then you want to test the primus by measuring the speed of light as you move toward a Galaxy that emits light. Hmm, do Galaxies emit light? My understanding is that Andromeda is already moving toward us. We can conduct the measure as is and the conditions are already met. Is a light year a velocity or a distance? Because of the way you worded it the distinction might make a difference if we are going to allow that the primus of c being invariant is incorrect. Perhaps you meant that the light would reach us sooner rather than faster? Just wondering?
Strange Posted November 1, 2018 Posted November 1, 2018 ! Moderator Note Discussion of semiconductor manufacturing technology moved to here: https://www.scienceforums.net/topic/116814-semiconductor-fabrication-split-from-do-objects-move-faster/ (partly as a test of my new powers!)
Menan Posted November 1, 2018 Posted November 1, 2018 9 hours ago, Strange said: As I have spent a large part of my career designing CPUs I know this not true. But you carry on with your irrational beliefs. Every CPU was designed to correct for a fault in the previous generation or to achieve better size and power usage. No quantum theory is used in this process,
koti Posted November 1, 2018 Posted November 1, 2018 3 minutes ago, Menan said: Every CPU was designed to correct for a fault in the previous generation or to achieve better size and power usage. No quantum theory is used in this process, Which part of "Discussion of semiconductor manufacturing technology moved to here" did you not understand?
Menan Posted November 1, 2018 Posted November 1, 2018 (edited) 7 minutes ago, koti said: Which part of "Discussion of semiconductor manufacturing technology moved to here" did you not understand? I guess the magical powers didn't actually move anything. But he knows where the universe came from Yup When you lose an argument move it to where it can't be seen. I do not have to move anything, because I have never lost You are not required to enjoy this I do Edited November 1, 2018 by Menan -2
Strange Posted November 1, 2018 Posted November 1, 2018 11 minutes ago, Menan said: But he knows where the universe came from No one knows where the universe came from. (If it came from anywhere.) 12 minutes ago, Menan said: When you lose an argument move it to where it can't be seen. It can be seen.
koti Posted November 1, 2018 Posted November 1, 2018 16 minutes ago, Menan said: I guess the magical powers didn't actually move anything. But he knows where the universe came from Yup When you lose an argument move it to where it can't be seen. I do not have to move anything, because I have never lost You are not required to enjoy this I do Wow. I must say you're a great test of Strange's new powers, there's not much more on the A hole scale than this ^ I'm sitting here trying to type something on topic but frankly I can't because you are lacking horribly in every single subject you touched so far...there's no knowing where to start explaining things to you with you not understanding or twisting everything that is being layed out for you. Did you at least come up with the fact that you weigh less on the Moon than on Earth but in both cases you have the same mass ?
jajrussel Posted December 7, 2018 Posted December 7, 2018 On 10/30/2018 at 9:58 PM, Menan said: But if you could remove by some means the weight of a mass, the amount of energy needed to move the mass would be reduced or eliminated and light speed might be possible. Laugh, but once Von Braun was laughed at by the brightest minds for proposing that it should be possible to shoot an object to the moon. He hadn't built squat yet, minus the bicycle with fireworks attached that is. We achieve faster than light speed, or die here How I know that no one really understands relativity. Because no one adds to it, or continues it in any way, its a dead field, like studying history, it can't change, real science is an unstoppable forward march and is not missing 85 percent of the equation If mass increases at light speed, why. Would atoms get bigger? or increase in number. ? It would seem to me that removing weight should be as simple as becoming an astronaut. Get away from gravity. If my understanding of black holes is correct, it would seem that what is needed is a lot of mass in a much smaller area, so I’m curious as to why things like atoms would get bigger? Actually, even atoms getting smaller sounds a little strange, but I am making the assumption that atoms need a certain amount of area in order to exist as atoms. Hmm? Is kinetic energy similar to fictional force? I once thought of the gravitational effect on a photon as a virtual effect, can the same sense be applied to kinetic energy to the effect that an increase in mass is a virtual effect? But, virtual or not I would think that by displaying mass a photon would present a change in acceleration displayed as a curve which when observed would appear as slowing down since a curved line between two points takes longer to transit than a straight line, but what do I know? My understanding is that if you add mass to a photon through a medium it slows down. It doesn’t go faster, so there’s no reason to think that FTL can be achieved by loosing weight and applying energy, but like I said what do I know?
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