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Physics

Do computers defy the law of conservation of mass? Because, if a computer can copy a program there is twice the amount of space taken up. But how can you just duplicate an amount of space (MB, KB, GB,etc.) if you add nothing to it?

The only mass involved in computer memory is the mass of the electronic components that make up the memory, and this mass is unchanged when information is stored in memory. If your computer has, say, 256 MB of memory, then it has memory chips inside it that are capable of holding 256 MB of information. When information is stored in memory, the physical state of those memory chips is changed, but no new mass is added. Perhaps an analogy will help. Imagine a row of ten coins sitting on a table. By letting tails represent 0 and heads represent 1, you could think of this row of coins as a primitive kind of memory, capable of storing a sequence of ten 0's and 1's. You would store such a sequence of 0's and 1's by flipping over some of the coins in order to get the appropriate sequence of heads and tails. Flipping the coins changes their physical arrangement, but not their mass. So mass is conserved during this operation.
Physics

Quantum behaviour says that before a phenomenon is observed there may be a number of possible outcomes. Once observed, the number of possible outcomes becomes one; what actually happened? Surely the present moment consists of an infinity of phenomena which, with the benefit of Quantum hindsight, may be seen to have *actually* been certainties. Uncertainty exists only in the mind of an imperfect observer; there’s no such thing as foresight outside of a limited, dry mathematical framework. This leads me to think the following; i) That everything is as it is because it could not possibly have been any other way. ii) All the things in the universe whose extremely improbable existence we marvel at and things which everything else depend on who, if they were any other way, lots of other things wouldn’t work either, were actually (in retrospect), absolute certainties. Is this a gross misunderstanding of Quantum theory, an obvious conclusion, or a line of thinking with some mileage? I can see it leading...

The problem you raise in your first paragraph is called the measurement problem : What happens when a measurement takes place? Most physicists would not agree with your statement that "Surely the present moment consists of an infinity of phenomena which, with the benefit of Quantum hindsight, may be seen to have actually been certainties." The way most physicists interpret quantum mechanics, the uncertainty about the outcome of a measurement is not "only in the mind of an imperfect observer," but rather in the world itself. For example, before you measure the position of a particle, it simply doesn't have a position. It's not just that we don't know its position, it's that it doesn't have a position. This interpretation seems to be forced on us by experiments like the famous two-slit experiment. In this experiment, particles are fired at a barrier with two slits in it, and then their positions are recorded when they strike a screen behind the barrier. These positions form an...
Physics
Science
Space

Science states that space is endless, and ever expanding. But, if we are inside the planet earth, the planet earth is inside the galaxy, the galaxy is inside space, then what is space inside? What is it expanding in? And if space is endless, how can it expand?

Space is not expanding "in" anything else. The distances between points in space are increasing, but not because they are moving through some "superspace" that contains space. Mathematicians distinguish between two different approaches to defining geometric properties of a space: the extrinsic approach and the intrinsic approach. The extrinsic approach involves relating the space to some larger space that it sits inside; the intrinsic approach makes use of only the space itself, and not some larger space that it sits inside. For example, suppose we want to study the curvature of the surface of the earth. One way to see that the surface of the earth is curved is to image a flat plane tangent to the surface of the earth at some point. We can detect and measure the curvature of the surface of the earth by noting that the surface deviates from the tangent plane, and measuring the size of this deviation. But this deviation takes place within the 3-dimensional space that the surface of the...