Questions from a layman

[villagearchitect]

Hello Guys and lady’s,<br /><br />I’m not even a layman in physics but have several burning questions that maybe someone can help me with.<br /><br />I asked my 9th grade science teacher 35 years ago about the true nature of gravity and he tasked me to report back the next day. He didn’t know. Newton’s equations & simplifications that a “force” was responsible didn’t satisfy my curiosity. Back then we laughed at the ancient scholars idea of an “ether”. Space was “nothing”. I came back with the “force between masses” Newtonian explanation. I cheated myself by not investigating further.<br /><br />I did a google search today for “gravity” and the term “force between masses” still comes up for about 90% of the responses, yes 35 years later. No wonder society is so science illiterate. <br /><br />I learned in liberal arts college about spacetime, warped space,etc. and if one is even mildly curious the cable science channels go into some current explanations which satisfy the curiosity of most people. I’ve explored a little deeper but still have some burning questions. Please help me out.<br /><br /><br />1. If I drop a ball from arms length is the ball falling through spacetime, falling with spacetime or is earth(mass) expanding,with the universe, at a greater rate than surrounding space. I doubt the latter and at least hope not in the case of black holes. Or are none of these correct?<br />2. Is there a center of the universe from which it can be determined the universe started/expanded from, and ,if the universe is expanding outward from a point of origin is the expansion linearly uniform or are the boundaries of the universe expanding at a greater rate than near the center or vise versa, of course discounting local anomalies? <br />3. I recently read an article that quoted “scientist” as saying gravity operates at the speed of light. What does that mean? Does it accelerate similarly?<br />4. Radiation seems to me to be contractions/disturbances in space fabric and matter

 

[contracommando]

<font color="yellow">2. Is there a center of the universe from which it can be determined the universe started/expanded from,</font><br /><br />1) Well, not exactly. Space is expanding, but not from a central point (which may seem counterintuitive, but I’ll explain). Imagine that the universe is a giant balloon, with all the galaxies, stars, and people living on the surface of this balloon (ignore the volume). Now draw dots on the surface and then blow it up even more; the dots all move away from each other, but not from a central point. The expansion happened everywhere between the dots. A similar thing happened during and after the big bang (and even to the present); space everywhere expanded. So, the big bang happened at all points in space…in the space in front of you as you read this, in the space between the pages of a book, in the space between Earth and Mars, etc. You could also reverse this process by releasing some air from the balloon and watching as the points converge in a big crunch.<br /><br /><font color="yellow"> and ,if the universe is expanding outward from a point of origin is the expansion linearly uniform or are the boundaries of the universe expanding at a greater rate than near the center or vise versa, of course discounting local anomalies? </font><br /><br />2) Generally, relative to us, galaxies further away are moving outward at a faster rate - exponentially (although the galaxy of Andromeda is moving towards us….this is because it is close enough for its gravity to influence the Milky Way is a significant manner). <br /><br />After the big bang, the universe expanded in an exponential fashion; this process slowly stopped and the universe began expanding at a slower rate, then the universe made a transition away from this and began to expand in an accelerated fashion which lasts to this day.<br /><br />For an example, imagine that you draw two dots near each other on the surface of a balloon, near its equator (the top

 

[harmonicaman]

<i>1. If I drop a ball from arms length is the ball falling through spacetime, falling with spacetime or is earth(mass) expanding,with the universe, at a greater rate than surrounding space.</i><br /><br />I'd go with "Falling through spacetime". Space is indeed expanding around us, but mass itself is not expanding... <br /><br /><i>2. Is there a center of the universe from which it can be determined the universe started/expanded from, and ,if the universe is expanding outward from a point of origin is the expansion linearly uniform or are the boundaries of the universe expanding at a greater rate...</i><br /><br />From your perspective, you are both the center and the edge of the universe; you are also the oldest and most rapidly expanding point in the universe! Unfortunately, every other point in the universe also shares this very same perspective!<br /><br />This is because the universe is (to put it simply) spacetime being created within an infinitely small singularity. Even though our singularity universe has infinite spacetime, it still maintains many of the attributes of the singularity within which it is expanding.<br /><br />Or looking at it another way; take away the dimension of time and you would be back at the singularity of our origin; and time is merely another manifestation of mass and energy (E=mc²).<br /><br />BTW - Current measurements seem to indicate that the expansion of the universe is accelerating and (the current mainstream scientific opinion is that) it will continue to expand forever... <br /> <br /><i>3. I recently read an article that quoted “scientist” as saying gravity operates at the speed of light.</i><br /><br />Measuring the speed of gravity has been a very difficult challenge to test and there are many conflicting arguments. Gravity traveling at "c" (the speed of light) seems logical, though.<br /><br />Note that gravity is merely the result of time interacting with mass and currently there are more questions than answers as to what

 

[yevaud]

<i>...there are several good (but depressing) essays on the web about what the universe will be like in several trillion years; probably very cold and dark...</i><br /><br />That's entropy for you. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[trisco]

good stuff, nice Q&A

 

[superluminal]

Very nice answers.<br />___________________________________________<br /><br /> 3. I recently read an article that quoted “scientist” as saying gravity operates at the speed of light. <br /><br />Measuring the speed of gravity has been a very difficult challenge to test and there are many conflicting arguments. Gravity traveling at "c" (the speed of light) seems logical, though. <br /><br />Note that gravity is merely the result of time interacting with mass and currently there are more questions than answers as to what the heck is going on with these two... <br /><br />I can't continue because my brain hurts, but do Google "Planck" - interesting reading there, and there are several good (but depressing) essays on the web about what the universe will be like in several trillion years; probably very cold and dark... <br /><br />_____________________________________________<br /><br /><br /><br /> I'll admit, that gravity and light speed being equal, seems very logical to the human scientific mind.<br /><br /> Perhaps though, distinguishing between the two speeds would be as hard as distinguishing exact electromagnetism poles.<br /> Or a single particle from another particle in the kelvin coldness of deep space.<br /><br />Seems logical then , that if only there was a way to achieve colder than kelvin temperatures outside the space station, <br /> Then possibly you would have a reliable instrument to measure the properties of the vacuum of space itself.<br /><br />Or possibly deep inside the individual layers of the Higgs Field. <br /><br /><br /> Any thoughts?<br /><br />One thing for sure is that properties of the Higgs Field offers answers.<br /><br />And gravity and mass acceleration are relative to each other, <br />It seems logical then, that if a ( mass) ( lets say in this case the mass is a human being ) could achieve zero velocity in relation to the movement of our entire solar system. Then a mass possibly would not need propulsion to achieve earth escape velocity. <div class="Discussion_UserSignature"> <p><br /><strong><font size="3" color="#3366ff">Columbia and Challenger </font></strong></p><p><strong><font size="3" color="#3366ff">Starships of Heroes</font></strong></p> </div>

 

[villagearchitect]

Thanks guys and ladies,<br /><br />I’ve gone through the responses and they are very good. I’m going over them again.... Thanks people.<br /><br />The thought that I might be both at the origin and now at the edge of the universe is very intriguing. I guess my understanding of the word singularity is now a block from being able to visualize this concept. I will dig deeper on this subject.<br /><br />I would like to rephrase one of the questions concerning releasing a ball at arms length.<br /><br />Is spacetime relatively static over the surface of the earth at a given height, except for dragging, or is spacetime flowing into the earth, being “consumed” by or perpetuating the existence of matter? <br /><br />The round mass on the mattress analogy doesn’t do much for me because of it’s 2D nature. In what we call 3d there must be a density differential in spacetime, causing a flow, for anything to move through it and in fact accelerate once released from “rest” unless of course the unlikely other alternative I mentioned in my original post were true. <br /><br />Is there another answer? <br /><br />Thanks,<br />DB<br />

 

[villagearchitect]

After drinking a cup of coffee I realized I had in fact said two different things in my last post.<br /><br />Spacetime flowing into the earth – probably wrong<br /><br />Differential in spacetime density- causing mass and energy to “ prefer to exist’ in the region of lesser density and thus Gravitate there. Space itself likely static except for influence of items/energy falling thru it - probably a more likely scenario. <br /><br />Am I on the right track here?<br />Thanks,<br />DB<br />

 

[villagearchitect]

Happy new year and welcome to 1984 + 22<br />Good luck to us and our children. <br />Db

 

[harmonicaman]

<i>"I’ve gone through the responses and they are very good.</i><br /><br />But how do you <i>really know</i> that? We could just be feeding you a stream of Bozo flux and in cosmology, todays facts and reality often turn into tomorrows pseudoscientific psycho-babble! Go figure...<br /><br /><i>"The thought that I might be both at the origin and now at the edge of the universe is very intriguing."</i><br /><br />Here's another way to look at it: The "Edge" of the universe is right in front of your nose at "c" (the speed of light). It's right there¹, but you can never reach it!<br /><br /><i>"Is spacetime relatively static over the surface of the earth at a given height, except for dragging, or is spacetime flowing into the earth, being “consumed” by or perpetuating the existence of matter?"</i><br /><br />That's a great philosophical conundrum and science is grappling for answers. It is unknown if "m" is absorbing or emitting spacetime, but I think the answer is likely neither and both. (Things aren't always how they seem in our universe.)<br /><br />Using the "Singularity Universe" model, "m" is merely resistant to the expansion of spacetime^2.. We observe this phenomenon as the curvature of spacetime in the presence of "m" and the result is expressed as gravity.<br /><br /><i>"The round mass on the mattress analogy doesn’t do much for me because of it’s 2D nature."</i> <br /><br />Me either; modelling higher dimensions is devilishly difficult. Note that the singularity universe is a one dimensional concept and all higher dimensions are in conflict with the singularity of our origin. <br /><br />When the big bang occurred, not only did mass and energy come into existence, but multidimensionality also started unfolding within the singularity; the universe is struggling to reach an impossible equilibrium between the "1" (the singularity) and "Infinity" (1+x^y dimensions within the singularity). <br /><br />This conflict is our universe!<br /><br />-