In the past year or so, I’ve almost completely abandoned reading fiction novels. Okay, not completely. I still love a good story and I won’t leave them behind forever (Just finished Water for Elephants, which is just fabulously entertaining), but my “real life” interests are just becoming so numerous that those dry, nonfiction books have taken over my world.
First there is my ashtanga yoga practice which draws me to books about the practice, the tradition, the people. I’ve been a sponge absorbing all I can. Yoga has done an entire reordering of my mind and body. And it just makes me feel great! (This is another post entirely, so more on that later).
Then I have my changing perspective on my role on this planet. I’ve been reading books such as “Field Notes from a Catastrophe,” “Silent Spring,” “The Story of Stuff,” even parts of Aldo Leopold’s “A Sand County Almanac.” For those Wisconsinites reading this post, it’s interesting to know Leopold was a professor at UW and was critical in the original development of environmental ethics. His book poetically describes the changing seasons in Sauk County, WI.
I’m still eating up the Biology books too. Especially those focusing on the evolution of life on Earth. I am continuously amazed by the creations that have lived on this planet and how they have been influenced by each other and the changing landscape. Inevitably that led to Richard Dawkins. Again, another story entirely.
So, finally that brings me to the point of this post. I am currently reading an incredible book called “The Elegant Universe” by Brian Greene (physicist from Columbia University). I must have walked past it a million times at the book store before I finally purchased it. And then it sat around quite a bit longer on my shelf before I eventually got around to opening it up. What inevitably motivated me to read it was a series of conversations (maybe debates is more appropriate) I’ve been having with Eric.
It started with black holes. We were basically arguing about whether or not it’s possible to enter a black hole and if it in fact will lead to another dimension or allow us to time travel. Since neither of us knew what we were talking about, it was more a regurgitation of “facts” we had seen in science fiction movies :). So before our next conversation, we both did some studying (since we like being knowledgable and right all the time :) ). And what I found out is... this stuff is cool! The answer to the first part of our debate is a resounding No. Humans cannot enter a black hole. Our bodies would be ripped apart due to the exponential increase in gravity as we approach the black hole. It’s called, quite appropriately, “spaghettification.” Well, I guess actually we could enter a black hole, but rather in pieces :)
But the answer to the second part of the question (other dimensions, time travel, etc.), I don’t think we can quite be sure. This intrigued me so much I found myself studying Einstein’s theory about how gravity warps space and time. I mean I guess I see how gravity warps “space” (I can see these effects), but I didn’t quite get the “time” thing (still don’t think I do). But the idea is this; Lets say it were possible and I could safely approach a black hole. Lets say I had a rope from a space craft and lowered myself as close as a could to a black hole and hung out there for a year or so. Then I climb back up my rope, get in the space craft, and head back to Earth (ignore the travel distance). What I would find is that while I only spent a year according to my watch hanging out by the black hole, maybe 60 years or so would have passed on Earth! My sister would now be 55 years my senior (sorry Lyffa :) )! Theoretically, this is the type of “time travel” Einstein says happens all the time, just on a scale way too incredibly small for us to notice.
AND, we have experimental evidence that repeatedly supports this idea!
Okay, if you don’t think this is cool, I don’t know what more I can do for you. This is incredible information about the universe we live in every day and don’t notice!
I am SOOOOO hooked. Which is why I finally started reading “The Elegant Universe.” All I knew what that this book is about ‘the string theory,’ physicsy stuff, but I had no clue what it was. Still don’t. But this makes it all the more intriguing. The book’s purpose is to make this idea of string theory, or ‘theory of everything’, at least somewhat understandable to the common man (or in this case, woman). I’m only in the first half of the book, and it has hardly even talked about string theory. At the beginning, the author Brian Greene is just laying down some foundation.
The idea is this; we have a bunch of ‘rules’ (laws of physics) that we can apply to very large things (the universe) and we have rules we can apply to very small things (atomic particles/quantum mechanics). The thing is, they don’t actually make any sense in light of each other. Shouldn’t we be able to come up with ‘rules’ that apply to all these physical phenomena? Physicists think so and even think they might have a solution: String Theory.
All very exciting, except I have no idea what they are talking about. What are the ‘rules’ we use for objects in the universe? What are the ‘rules’ we use for atomic particles? That’s exactly what Brian Greene is currently trying to teach me. I just finished the large-scale, universe stuff and it is all about Einstein and his theory on general and special relativity. Here are the the two most cool things I learned so far (sorry, brian, for stealing some of your descriptions):
1. The faster you travel, the slower your time passes compared to someone else at rest.
Yes, it’s true. The faster you go, the slower your clock ticks compared to someone else’s clock at rest. Since you are now moving through space, the increase in distance makes the time that paces look longer to someone observing you. Einstein explained this very easily using the ‘light clock’ analogy, which I won’t regurgitate here, but very interesting and easy to understand if you look it up!
What’s also interesting is that you don’t perceive yourself to be moving slower. Your time passes by just as it always does. Even more interesting is the fact that you only know you are in motion because you see objects zip by you as you move past. What if all the other objects are moving and you are in fact the thing at rest? This could actually be the case. Being at ‘rest’ or in ‘motion’ is completely relative to another object. So your observer may see you moving and see your clock ticking slower. But you may have the opposite perspective and think that you are at rest and your observer is in motion and their clock is ticking slower. Contradictory? Yes and no. If you read this book it will explain how both perspectives are in fact correct!!
Now why don’t we experience this motion and ‘time slowing’ in real life? Because we never travel fast enough for it to make even the tiniest of a noticeable difference. For this time difference to be significant to use we would have to be traveling at speeds near that of light (186,282 miles per second). Yeah, so really, really fast.
Now reading this, don’t you feel like you spent your life being tricked? We think we understand our physical reality so well and we have just simply no clue. For me, it is incredibly humbling. How tiny, insignificant we are and how truly warped our view or reality is. And if you think that is a crazy concept, it gets worse:
2. Everything is always traveling at the speed of light.
No, it’s not a typo. The idea is that literally everything is always traveling at 186,282 miles per second. You, sitting in that chair are currently traveling at light speed. That car zipping by is also traveling at light speed. The fly buzzing by, the jet plane, the sun, the entire Earth; all traveling at the speed of light. Always. Even if they seem to slow down or speed up in their travel through space.
Here’s why. We are thinking about speed only one-dimensionally. We think of the speed of something as how far it travels in a unit of time. For example, ‘the car traveled 10 meters from point A to point B in one second.’ But this example doesn’t consider that while the car is traveling through space from point A to point B, it is also traveling through time. So there is always at least four dimensions to your travel; three through space (right/left, forward/backward, up/down) and one through time. Together your speed is a combination of all four dimensions. So if you are currently sitting still, then you don’t have any speed through space and all you ‘travel’ is through time alone. Thus time seems to pass more quickly for you than moving objects around you. Now, if you start moving then some of your ‘travel’ is now through space. We have to subtract that from you ‘travel’ through time so that your total speed is always light speed. Thus, the faster and faster you travel through space, the slower you are traveling through time.
But what about a photon of light itself which is already traveling through space at light speed? Since all its speed of travel is through space, then the speed of travel through time is zero. Meaning, time does not pass for a photon of light! Light formed upon the origin of the universe still exists today in its original form. Theoretically this makes sense and has also been physically confirmed through astronomy.
Okay, I hope I didn’t bore you too much :). Thanks for reading this far! I get so pumped up by this stuff. If you’re interested at all, I highly suggest you pick up a copy of “The Elegant Universe” (or a kindle version and save the environment :)). I’m telling, very cool, incredible stuff. Is it too late to go back and get a degree in Physics?
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