hardcore string theory

Philosophy Forums Science, Technology, and Math
1

there are a couple of things that i dont understand after reading the Elegant Universe

how does string theory explain time dilation?

it seemed that in the book, Greene describes how since the string is not a point particle, the particles enter the perception cone of the observer at an angle, and not all at once? i dont get it.

also it seems like an explanation of time dilation would require an explanation of why the speed of light is constant. but i dont know, i really have no idea what he meant in this section and i gave the book away a while ago.

the other thing i didnt finish understanding was the inverse radius duality and what its implications are

he talks about how ‘wound’ strings (strings wound around the outside of the universe, not floating around inside?) are defined by how much energy is in their vibration, and how large their radius is. they are defined by a combination of these things, and there are two different combinations that yield the exact same observable results, for each observable result. (ie vibration=1,radius=5, appearance=blue;; vib=3,rad=2, appearance=also blue, indistinguishable)

the equivalent partner of each combination lies on the other, inverse, side of the tiny planck length. (ie, if a string has a radius ten times the planck length and some amount of vibration, and its blue, then a string 1/10 the PL with some different amount of vibration is also blue)

if an atom (or a proton i forget) was the size of the solar system (or the universe i forget) then the planck length would be the size of a tree.

so is he merely describing a crazy math trick as so much string theory appears? or is the underlying math actually trying to say that in the tiny dimensions that exist inside the planck length, there can be a universe that is exactly like ours? that the big bang came out of their big crunch? containing particles that are exactly like ours but differing only in that they are unimaginably smaller?

what are some crazy sounding things string theory says that are interesting?

2

hey, ive watched greene’s episode on the string theory and such on Nova on PBS. i don’t really know too much about it in detail just that, kinda as you mentioned, strings are the smallest portion of atoms (smallest after quarks). all strings have a different vibration. you are right about that proton thing (except i think was an atom). if an atom were as big as our universe right now the strings would be as big as trees. we will never be able to see strings (for obvious reasons). actually strings were dicovered in the process of trying to finish Einstien’s study of how the weak, strong, eletro-magnetic, and gravitational forces lived together in the universe. but to answer your question strings were discovered, after many mathmatical anomalies, by an ancient mathimatical formula. hope that somewhat answers your question!

3

String theory doesn’t really need to explain time dilation, since general relativity does that just fine. I think string theory merely has to coexist with GR and not contradict it.

Yes, string theory does seem like mathematical slieght of hand, but of course that doesn’t mean that it couldn’t be true. It does verge on philosophy, or at least thats the knock on it. Perhaps at some far flung time in the future science may have methods adequate to the task of quantifying strings or at least perceiving them.

It has a certain elegance to it that I could certainly have found appealing were I the one to have created this little multiverse we have.