Hello there mates...
First of all, I want you to excuse me for my English, as it's not my mother tongue so I might have some mistakes...
I'm not a scientist, however I'm very interested on it, I'm a passionate of science and I'd like to get to understand a bit more some matters that are not totally clear... Let's see if you can help me.
So my questions are:
According to what I've understood, gravity is a force that is made out of the planet/satellite/star bending the universe (I've seen the example on the Internet of having a blanked straight and putting something heavy on it, so it'd make a "bend" and would somehow attract whatever is close), and due to this, time is also altered. From here come my two questions:
1. If every planet/star/satellite alters the space somehow, does that mean that EVERYTHING (including humans, or phones, or computers: everything that has a mass) alters also the space? even in the most minimum way? Do we create some kind of gravity on the things that might be close to us (even if it's not enough to totally attract it)?
2. If planets bend the space and the time, wouldn't that mean that the bigger the planet is, the bigger the bend would be and for this reason, the higher the gravity and the faster the time? Why do all planets have different gravity independently on how big they are?
QUOTE (jazzman_bcn+Aug 14 2009, 09:02 AM)
1. If every planet/star/satellite alters the space somehow, does that mean that EVERYTHING (including humans, or phones, or computers: everything that has a mass) alters also the space? even in the most minimum way? Do we create some kind of gravity on the things that might be close to us (even if it's not enough to totally attract it)?
2. If planets bend the space and the time, wouldn't that mean that the bigger the planet is, the bigger the bend would be and for this reason, the higher the gravity and the faster the time? Why do all planets have different gravity independently on how big they are?
Hello there! To answer both of your questions: gravity is a product of mass; every particle of matter has a gravitational pull. Gravity is the force of attraction. Every particle is attracted to every other particle with this weak (compared to the magnetic) force. Obviously, the more massive an object is, the greater it's gravitational pull. Your body's gravitational pull is small compared to that of the Earth's, so objects fall toward the Earth instead of you. If you took two coins and floated them in a vacuum far away from any other object, the two coins would 'fall' toward each other.
2. If planets bend the space and the time, wouldn't that mean that the bigger the planet is, the bigger the bend would be and for this reason, the higher the gravity and the faster the time? Why do all planets have different gravity independently on how big they are?
Hello there! To answer both of your questions: gravity is a product of mass; every particle of matter has a gravitational pull. Gravity is the force of attraction. Every particle is attracted to every other particle with this weak (compared to the magnetic) force. Obviously, the more massive an object is, the greater it's gravitational pull. Your body's gravitational pull is small compared to that of the Earth's, so objects fall toward the Earth instead of you. If you took two coins and floated them in a vacuum far away from any other object, the two coins would 'fall' toward each other.
Time doesn't exist.
flyingbuttresman,
gravity is a product of motion of mass. there is only pull when the motion gets substantial enough. At this point this is a strong force. Smaller masses will pull more.
And coins will repell each other ina vacuum, due to antiparticle pairs.
flyingbuttresman,
gravity is a product of motion of mass. there is only pull when the motion gets substantial enough. At this point this is a strong force. Smaller masses will pull more.
And coins will repell each other ina vacuum, due to antiparticle pairs.
QUOTE (O_o+Aug 14 2009, 09:16 AM)
Time doesn't exist.
gravity is a product of motion of mass. there is only pull when the motion gets substantial enough. At this point this is a strong force. Smaller masses will pull more.
And coins will repell each other ina vacuum, due to antiparticle pairs.
You ignorant fool. Go away. You are nothing but a science-hating troll.
gravity is a product of motion of mass. there is only pull when the motion gets substantial enough. At this point this is a strong force. Smaller masses will pull more.
And coins will repell each other ina vacuum, due to antiparticle pairs.
You ignorant fool. Go away. You are nothing but a science-hating troll.
pardon? is there something you do not comprehend? or is abuse just all you can say?
I suggest you take your time out to do some reading. The internet is a wealth of resources.
I suggest you take your time out to do some reading. The internet is a wealth of resources.
QUOTE (O_o+Aug 14 2009, 09:38 AM)
pardon? is there something you do not comprehend? or is abuse just all you can say?
I suggest you take your time out to do some reading. The internet is a wealth of resources.
You made 3 statements. All 3 statements were completely and utterly in error, as confirmed by experiment. If you had taken any time at all to study ACTUAL science, you would have known better. The internet is a wealth of resources to those who know where to look for legit information. This appears to be a skill that you have not mastered.
I suggest you take your time out to do some reading. The internet is a wealth of resources.
You made 3 statements. All 3 statements were completely and utterly in error, as confirmed by experiment. If you had taken any time at all to study ACTUAL science, you would have known better. The internet is a wealth of resources to those who know where to look for legit information. This appears to be a skill that you have not mastered.
Jazzman,
First off ignore O_o, he's what we call a 'crank', which is to say that he's read a tiny little bit about science and thinks he knows all the answers, without ever bothering to educate himself or (heaven forbid) get an actual education in physics. Any statement a 'crank' makes about physics is very likely to be completely wrong.
First off ignore O_o, he's what we call a 'crank', which is to say that he's read a tiny little bit about science and thinks he knows all the answers, without ever bothering to educate himself or (heaven forbid) get an actual education in physics. Any statement a 'crank' makes about physics is very likely to be completely wrong.
QUOTE (jazzman_bcn+Aug 14 2009, 09:02 AM)
1. If every planet/star/satellite alters the space somehow, does that mean that EVERYTHING (including humans, or phones, or computers: everything that has a mass) alters also the space? even in the most minimum way? Do we create some kind of gravity on the things that might be close to us (even if it's not enough to totally attract it)?
Yes, this is exactly right. All mass warps spacetime. More massive objects warp spacetime more than less massive objects. Your body is warping spacetime right now, albeit to such a small degree that it's not even measurable to our current level of technology.
It's not really independent on how 'big' they are. Gravity can be thought of as a field which surrounds each massive particle. When several particles are in close proximity (as they are in solid, liquid or gaseous objects such as planets) those fields combine to produce a stronger field. The further away from the center of mass of an object you move, the weaker the gravitational field is. More massive objects will have a stronger gravitational field, and objects with the a certain mass but a small volume will have a stronger field at their surface than an object with the same mass in a larger volume, meaning that small, dense objects will have the strongest fields, while large objects of a low density will have the weakest fields.
A black hole is an example of an extremely small, dense object. It's gravitational pull is so strong that not even light can escape it's surface. On the other end of the spectrum, a gas nebula will be so diffuse that it's gravitational field will not (or barely) even be measurable.
Yes, this is exactly right. All mass warps spacetime. More massive objects warp spacetime more than less massive objects. Your body is warping spacetime right now, albeit to such a small degree that it's not even measurable to our current level of technology.
QUOTE
2. If planets bend the space and the time, wouldn't that mean that the bigger the planet is, the bigger the bend would be and for this reason, the higher the gravity and the faster the time? Why do all planets have different gravity independently on how big they are?
It's not really independent on how 'big' they are. Gravity can be thought of as a field which surrounds each massive particle. When several particles are in close proximity (as they are in solid, liquid or gaseous objects such as planets) those fields combine to produce a stronger field. The further away from the center of mass of an object you move, the weaker the gravitational field is. More massive objects will have a stronger gravitational field, and objects with the a certain mass but a small volume will have a stronger field at their surface than an object with the same mass in a larger volume, meaning that small, dense objects will have the strongest fields, while large objects of a low density will have the weakest fields.
A black hole is an example of an extremely small, dense object. It's gravitational pull is so strong that not even light can escape it's surface. On the other end of the spectrum, a gas nebula will be so diffuse that it's gravitational field will not (or barely) even be measurable.
I'm sorry if this irritates people, but I'm going to keep posting my questions until they are sufficiently answered.
If space-time is compressed and bent by the strong gravity of a massive object, then couldn't one also say it is expanded in places distant from any massive objects?
In such expanded areas of space-time, wouldn't light take a long-time to travel distances that would appear much shorter in the compressed space-time surrounding a star or planet?
So, for example, is it possible that the planet Pluto is traveling in an expanded space-time orbit that makes it appear to be very far and take a long time to orbit when, in fact, if you control for gravitation it would be in a much shorter and faster orbit?
In such areas of expanded space-time, why would it be that rocket-propulsion would not make it possible to propel objects at speeds faster than light, since the same rocket was able to travel very fast within the strong gravitational field of more compressed areas of space-time?
If space-time is compressed and bent by the strong gravity of a massive object, then couldn't one also say it is expanded in places distant from any massive objects?
In such expanded areas of space-time, wouldn't light take a long-time to travel distances that would appear much shorter in the compressed space-time surrounding a star or planet?
So, for example, is it possible that the planet Pluto is traveling in an expanded space-time orbit that makes it appear to be very far and take a long time to orbit when, in fact, if you control for gravitation it would be in a much shorter and faster orbit?
In such areas of expanded space-time, why would it be that rocket-propulsion would not make it possible to propel objects at speeds faster than light, since the same rocket was able to travel very fast within the strong gravitational field of more compressed areas of space-time?
(edit)
Never Mind.
Thanks MjolnirPants, you explained it in much better detail.
Never Mind.
Thanks MjolnirPants, you explained it in much better detail.
QUOTE (light in the tunnel+Aug 14 2009, 12:40 PM)
If space-time is compressed and bent by the strong gravity of a massive object, then couldn't one also say it is expanded in places distant from any massive objects?
Expanded relative to what?
The contracted space? Yes.
It's not just space, but spacetime which would be "expanded". Sure it takes light "longer" to travel through such a region, but then again, in such a region, each tick of a clock takes "longer" by the same exact ratio, so the speed of light remains constant.
It's not just space, but spacetime which would be "expanded". Sure it takes light "longer" to travel through such a region, but then again, in such a region, each tick of a clock takes "longer" by the same exact ratio, so the speed of light remains constant.
So, for example, is it possible that the planet Pluto is traveling in an expanded space-time orbit that makes it appear to be very far and take a long time to orbit when, in fact, if you control for gravitation it would be in a much shorter and faster orbit?
No. The spacetime warping is quite small, and wouldn't make much of a difference. You're talking about differences on the order of a few inches to a few yards.
Because the only "speeding up" or "slowing down" of light that happens in a vacuum isn't really a speeding up or slowing down. It's a dilation (positive or negative) of time. You have to understand that there is no absolute time. There is no point in the universe where the rate of time you are experiencing is "right" or the "true" rate of time. As a consequence, there is no such thing as "true" simultaneity. What you and I perceive as happening right now, an alien with a powerful telescope on a planet a thousand light years away perceives as happening a thousand years from now. When light "slows down" in an "expanded" region of space, the new rate of time's passage is just as valid as the old rate.
You really need to read the following links:
http://en.wikipedia.org/wiki/Introduction_...cial_relativity
http://en.wikipedia.org/wiki/Special_relativity
http://en.wikipedia.org/wiki/Introduction_...eral_relativity
http://en.wikipedia.org/wiki/General_relativity
http://en.wikipedia.org/wiki/Time_dilation
http://en.wikipedia.org/wiki/Relativity_of_simultaneity
Read through them as thoroughly as possible, and when you're done any questions you have will be gladly answered by those here. Even the rudest member who knows physics will happily answer any question posed in good faith by a person who's shown they're willing to learn. When you refuse to use the resources you have, and instead expect others to simply give you the answers to your questions as you think of them, all you're doing is proving that you're too lazy to educate yourself, and demonstrating that any effort on our part to help you educate yourself will be wasted.
Expanded relative to what?
The contracted space? Yes.
QUOTE
In such expanded areas of space-time, wouldn't light take a long-time to travel distances that would appear much shorter in the compressed space-time surrounding a star or planet?
It's not just space, but spacetime which would be "expanded". Sure it takes light "longer" to travel through such a region, but then again, in such a region, each tick of a clock takes "longer" by the same exact ratio, so the speed of light remains constant.
QUOTE (->
| QUOTE |
| In such expanded areas of space-time, wouldn't light take a long-time to travel distances that would appear much shorter in the compressed space-time surrounding a star or planet? |
It's not just space, but spacetime which would be "expanded". Sure it takes light "longer" to travel through such a region, but then again, in such a region, each tick of a clock takes "longer" by the same exact ratio, so the speed of light remains constant.
So, for example, is it possible that the planet Pluto is traveling in an expanded space-time orbit that makes it appear to be very far and take a long time to orbit when, in fact, if you control for gravitation it would be in a much shorter and faster orbit?
No. The spacetime warping is quite small, and wouldn't make much of a difference. You're talking about differences on the order of a few inches to a few yards.
QUOTE
In such areas of expanded space-time, why would it be that rocket-propulsion would not make it possible to propel objects at speeds faster than light, since the same rocket was able to travel very fast within the strong gravitational field of more compressed areas of space-time?
Because the only "speeding up" or "slowing down" of light that happens in a vacuum isn't really a speeding up or slowing down. It's a dilation (positive or negative) of time. You have to understand that there is no absolute time. There is no point in the universe where the rate of time you are experiencing is "right" or the "true" rate of time. As a consequence, there is no such thing as "true" simultaneity. What you and I perceive as happening right now, an alien with a powerful telescope on a planet a thousand light years away perceives as happening a thousand years from now. When light "slows down" in an "expanded" region of space, the new rate of time's passage is just as valid as the old rate.
You really need to read the following links:
http://en.wikipedia.org/wiki/Introduction_...cial_relativity
http://en.wikipedia.org/wiki/Special_relativity
http://en.wikipedia.org/wiki/Introduction_...eral_relativity
http://en.wikipedia.org/wiki/General_relativity
http://en.wikipedia.org/wiki/Time_dilation
http://en.wikipedia.org/wiki/Relativity_of_simultaneity
Read through them as thoroughly as possible, and when you're done any questions you have will be gladly answered by those here. Even the rudest member who knows physics will happily answer any question posed in good faith by a person who's shown they're willing to learn. When you refuse to use the resources you have, and instead expect others to simply give you the answers to your questions as you think of them, all you're doing is proving that you're too lazy to educate yourself, and demonstrating that any effort on our part to help you educate yourself will be wasted.
QUOTE (O_o+Aug 14 2009, 03:16 PM)
And coins will repell each other ina vacuum, due to antiparticle pairs.
Whether two metal plates attract or repel one another depends on the configuration of the system. And it's not due to 'antiparticle pairs', it's due to matter/antimatter pairs.
When trying to fool people into thinking you know more than you do, it's best to check your facts first.
Whether two metal plates attract or repel one another depends on the configuration of the system. And it's not due to 'antiparticle pairs', it's due to matter/antimatter pairs.
When trying to fool people into thinking you know more than you do, it's best to check your facts first.
QUOTE (MjolnirPants+Aug 14 2009, 03:30 PM)
Jazzman,
First off ignore O_o, he's what we call a 'crank', which is to say that he's read a tiny little bit about science and thinks he knows all the answers, without ever bothering to educate himself or (heaven forbid) get an actual education in physics. Any statement a 'crank' makes about physics is very likely to be completely wrong.
Yes, this is exactly right. All mass warps spacetime. More massive objects warp spacetime more than less massive objects. Your body is warping spacetime right now, albeit to such a small degree that it's not even measurable to our current level of technology.
It's not really independent on how 'big' they are. Gravity can be thought of as a field which surrounds each massive particle. When several particles are in close proximity (as they are in solid, liquid or gaseous objects such as planets) those fields combine to produce a stronger field. The further away from the center of mass of an object you move, the weaker the gravitational field is. More massive objects will have a stronger gravitational field, and objects with the a certain mass but a small volume will have a stronger field at their surface than an object with the same mass in a larger volume, meaning that small, dense objects will have the strongest fields, while large objects of a low density will have the weakest fields.
A black hole is an example of an extremely small, dense object. It's gravitational pull is so strong that not even light can escape it's surface. On the other end of the spectrum, a gas nebula will be so diffuse that it's gravitational field will not (or barely) even be measurable.
Thank you all for your explanations! I've clarified my doubts!
Any other question i'll have, i'll deffo come here to ask 
First off ignore O_o, he's what we call a 'crank', which is to say that he's read a tiny little bit about science and thinks he knows all the answers, without ever bothering to educate himself or (heaven forbid) get an actual education in physics. Any statement a 'crank' makes about physics is very likely to be completely wrong.
Yes, this is exactly right. All mass warps spacetime. More massive objects warp spacetime more than less massive objects. Your body is warping spacetime right now, albeit to such a small degree that it's not even measurable to our current level of technology.
It's not really independent on how 'big' they are. Gravity can be thought of as a field which surrounds each massive particle. When several particles are in close proximity (as they are in solid, liquid or gaseous objects such as planets) those fields combine to produce a stronger field. The further away from the center of mass of an object you move, the weaker the gravitational field is. More massive objects will have a stronger gravitational field, and objects with the a certain mass but a small volume will have a stronger field at their surface than an object with the same mass in a larger volume, meaning that small, dense objects will have the strongest fields, while large objects of a low density will have the weakest fields.
A black hole is an example of an extremely small, dense object. It's gravitational pull is so strong that not even light can escape it's surface. On the other end of the spectrum, a gas nebula will be so diffuse that it's gravitational field will not (or barely) even be measurable.
Thank you all for your explanations! I've clarified my doubts!
Any other question i'll have, i'll deffo come here to ask
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