A most powerful idea in computation is that the program and the data can be one and the same. (That this distinction is often lost in higher level programming languages is a shame.) Thus a program which is some form of data can manipulate the data which is itself part of the future program. We often like to speculate that the universe may act like some form of a (possibly quantum) computer. What is interesting, then, about this “universe computer” is that it does not appear to be merging program and data in any way. The machine language of the universe does not manipulate its own program. Sure, at some higher level the universe does have the ability to manipulate its own program (for the universe does allow for us to build a computer!), but at its most fundamental level, there is not manipulation of the program. Or at least this is the fashion in which we think about the physics of the universe: there are laws which are the fundamental program and there is data which is the state of the universe. The program then acts to change this state of the universe over and over again, producing the evolution of the universe. But what if this is not the way the universe works? What if there is no distinction between the data and and the program in the universe? There can still be a state, and there can still be evolution of this state, but the laws of this evolution will depend on the past executed program. The laws in there most general form can not only change in time, but they will be a function of the past history (past program) of the universe.
Just as Reimann’s realization that we can define curved spaces without reference to any higher dimensional space into which this space curves, perhaps the lesson of computer science should be that we can think about a computer without a physical device to carry out the computation. We can think of the universe as a von Neumann computer in all its abstract glory of such a machine without actually believing that such a universe computer exists.
OK, I’ve clearly stumbled into crank land with this “creature of eager speculation.” But damn straight I’ve stumbled into crank land.
We Live in Dick's World
From Valis by Philip K. Dick:
“To fight the Empire is to be infected by its derangement. This is a paradox; whoever defeats a segment of the Empire becomes the Empire; it proliferates like a vius imposiing its form on its enemies. Thereby it becoes its enemies.”
Publish Noise
From an interview with Neal Stephenson:
Hooke, for example, when he figured out how arches work, published it as an anagram. He condensed the idea into this pithy statement: “The ideal form of an arch is the form of a chain hanging, flipped upside down.” Then he scrambled the letters to make an anagram and published it. That way, he wasn’t giving away the secret, but if somebody came along a few years later and claimed that they’d invented it, he could just unscramble what he’d published. He was establishing precedence.
How long until someone publishes a paper on the arXiv which is just noise and then, after some major result appears, says “No, I did this a long time ago, and here is the key which unscrambles my paper?
Pepper
Goodbye Pepper. You threw up on me (twice!) on the ride home from where we picked you out. You herded the washing machine and the lawn mower. You barked at everyone except family. Mostly you snored loudly. The floor will be a little dirtier, the days a little quieter, and the washing machine will be much much lonelier. RIP Pepper (1995-2004)
Silly Questions
The number one most irritating question I was asked during my faculty interviews was “what will you do if quantum computation doesn’t pan out?” At first glance this question seems perfectly valid: a department should concern itself with whether they are hiring someone whose work will quickly become irrelevant. But I’ve got news for you all, quantum computing’s not going away! Why? Well not for the reason the question askers are thinking: what happens if a quantum computer can’t be built? No, quantum information science will stick around because it has an intrinsic intellectual value. And this is what makes the question so irritating: it implies that quantum information science is a fad with no intrinsic intellectual value. Do you ask string theorists whether what they do will be experimentally testable and if not what will they do? Do you ask astrophysicists whether studying cosmology will have any significant impact on society? No. But because these are part of a long tradition of theoretical physics they are acceptable intellectual persuits, whereas quantum information science, being new and getting too much press is most definitely suspect.
There is, of course, great irony in this situation. Theoretical physics has always justified a large portion of it’s work as for the greater intellectual good (holier-than-thou-physics.) But mention the word “quantum” all of a sudden normally elitist physicists turn into engineers. The psychology behind this is pretty simple in my opinion (wait this whole thing is my opinion!): physicists have yet to actually accept quantum theory. They don’t want to think about it because it’s strange. The fact that it’s current position is basically to serve as the operating system of the universe doesn’t help at all. Because we can separate the axioms of quantum theory nicely from the physics of the fundamental forces most physicists can spend their entire life living, breathing, and calculating classically. Rather embarrasing for a group which seeks to understand the fundamentals of our universe.
Living In LA Is Like Smoking
Today I sent in my acceptance for a postdoc at the Santa Fe Insitute. 16 miles to Ski Santa Fe and 72 miles to Taos.
Antonyms
If theodicy is “defense of God’s goodliness and omnipotence in view of the existence of evil,” what word describes “defense of God’s evil and falibilty in view of the existence of good?”
Bootstraping Our Way
Suppose Alice and Bob perform a test of a Bell inequality. They start together and produce an entangled quantum state. Then the parties move apart such that when they make their measurements on the entangle quantum state they are spacelike separated and are at rest with respect to each other’s motion. Let’s suppose that Alice and Bob perform their measurements at the same time (simultaneous) according to the two party’s rest frames. Now the standard paradox arises: the correlations Alice and Bob produce cannot be explained by a local hidden variable model: one party needs to produce an outcome which is predicated on the measurement choosen by the other party. So this seems very bad: if Alice sends a signal to Bob at the speed of light, immediately as she does her measurement, then the signal will arive at Bob at a time equal to the distance between the parties divided by the speed of light. But now look at exactly just this scenario from the perspective of a party who is traveling in a reference frame which is moving with a velocity in the same direction as the separation of Alice and Bob. If this frame is moving at nearly the speed of light with respect to rest frame of the parties, then the paradox seems almost triffling: in this frame of reference, Bob would get the information immediately after he would normally need it. Extrapolating as this party’s frame’s velocity goes to the speed of light and thinking that there is a limit to how sharply we can define when a measurement occurs, we see that “There exists a reference frame in which the paradox of Bell violation for all practical purposes disappears.”
What does this tell us? Well it certainly doesn’t resolve the Bell paradox. One thing to get is that the paradox is reference dependent. OK, not too interesting either. But what I think is neat about this thought experiment is it gives us a point of little or no paradox upon which we can begin to think about how to bootstrap our way into the reference frame where there is a very measurable Bell paradox. How do we do this? Heck if I know: the point is mostly that the solution should be a SMOOTH map from this little or no paradox reference frame to the frame where the information propogation is ridiculous.
A Koan
Email from a master:
Two theorists were walking through the forest of quantum mechanics.There they came across an ATM machine.
In front of the ATM machine was a long line of experimentalists.
The student asked,
“Surely master an ATM machine deep in the forest of Quantum Mechanics must have an incredible surcharge.”
The master,
“Can the hive steal money from a single bee?”
The student
“Without the bees, there is no hive.”
The master,
“Without the hive, there are no bees”
The student
“This honey is bitter”
The master,
“Fear not, we are not bees.
Blue Buddha
Today I learned that they offered the job I interviewed for in Vancouver to “an experimentalist.” Today is Buddha Day. Repeat after me: “I will not lose my Zen-Buddha nature, I will not lose my Zen-Buddha nature…”