I know that the strings of String Theory are unimaginably small, and I know that the universe is unimaginably large. My question is this:
Which am I closest to in size? I’m 5’11", 170lbs if it matters.
A string is about 35 orders of manitude smaller then you are, the observable universe is 26 orders of magnitude larger. So you’re bigger relative to a string then the universe is relative to you.
According to most string theories, the string needs to be on the order of the Planck length, which is about 10^-35 meters. The universe is at least 156 billion light-years wide, or about 5 x 10^26 meters. So proportionately, your size compared to a string is far greater that the size of the universe compared to you.
On preview, seems Supdog and I agree.
Currently the size of the observable universe is reaonably-well known, but in some models of the post-inflationary universe (assuming inflation holds up) the whole shebang might be much bigger, so if you want to boast accurately, phrase it this way: I am larger relative to a string than the observable universe is to me.
So if the OP and a bunch of his friends got together and started vibrating in unison, would they create a macroscopic particle that’s even larger than the universe?
What an unbelievable question! As I know very little about these topics, it’s not something I would ever have thought to ask or expected to ever encounter, but it’s pretty neat to now know the answer! Thanks for asking it!
And nitpicking my own answer: I am pretty sure a string does not have “volume” per se, while the universe kinda sort does, at least in the sense of the rough parallel of how many of you one could pack into a sphere 156B or so light-years across (and of course, the shape is ((probably)) not equivalent to a sphere). Since volume is sort of length cubed, it’s easiest to answer the question in terms of, say, your height versus planck length versus the (putative) diameter of the universe.
I await a more intelligent answer than mine.
Well, you’re about six feet longer than a string, and the universe is way longer than 12 feet, so I’d say you’re way closer to the size of a string than the size of the universe.
Heh.
“The whole shebang” is actually a fairly common expression among cosmologists, though I don’t know how much that’s influenced by it having the word “bang” in it. Mostly we say it because others say it.
For another interesting factoid, the Planck mass is about as far from a proton as a proton is from a star. Which gets even more interesting when you realize that it’s not a coincidence.
Thanks for the responses! I had a sneaking suspicion that this was the case, but that doesn’t make it any easier to fathom.
This response,
though, raised another question I have been wondering about for a long time.
If the universe is around 13.5 billion years old, and nothing travels faster than the speed of light, how can it be this big?
I’ve heard theories that during, and shortly after the Big Bang, that the “inflation” could have been faster than the speed of light. Is this why the universe can be the size that it is?
For arguments sake, let’s say the the Big Bang happened at the center of the observable universe and expanded outward at the speed of light. That would make the universe 27 billion light years wide. Right? Now lets say that for a brief period of time, the inflation was faster than the speed of light. It would be “wider” than 27 billion light years, but I wouldn’t think that it would be wider on the magnitude that it is.
How is this possible?
Because space is expanding.
As light travels the distance between it and you is increasing.
So if it travels 1 light year the space between you and it may have expanded 1/2 light year (or whatever depending how far away it is).
You shouldn’t think of the Big Bang as “This something exploded and shot all the matter out into space”. The thing that was expanding WAS space. The matter just happened to be embedded in it.*
*Layman’s understanding…if it’s wrong, let me know, please.
This might help illustrate the issue of space being bigger than 13.7 billion light years better (nifty little animation along with explanations).
What a perfect question: we have 2 completely opposite but correct answers.
I tossed in “the whole shebang” as an oblique reference to the book by Timothy Ferris–a favorite of mine. Worthwhile reading for some of the questions posted here; I might also recommend Brian Greene’s Fabric of the Cosmos. There are many others written for us lay cosmos gawkers.
A fun link recently posted in a Dope thread, possibly useful for the OP.
And the obligatory xkcd links…
OK, you’re going to have to explain the ‘not a coincidence’ part.
Is there any advanced layman reference you could give me for that?
Speaking of the big bang do you ever hear cosmologists refer to it as the 'Horrendous Space Kablooie" or HSK? This name was introduced by Calvin (or more precisely Bill Watterson in his comic strip Calvin and Hobbes). Wikipedia claims this alternative “has achieved some popularity among the scientific community, particularly in informal discussion”.
Now wait a second … I thought many versions of string theory include strings of many sizes, including cosmologically big. True the strings that are supposed to underlie bosons and all are Plank length but not all are.