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Joined 11 months ago
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Cake day: June 30th, 2023

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  • Not to mention the problem of what life is even supposed to do beyond a certain point of development. The depressing fact is that there is a finite amount of knowledge to be gained, a finite amount of resources to harvest, a finite diversity of life to contend or thrive alongside with. Once a pocket of life in this massive universe begins to run out of things to do and stagnates, then what? What is there to think about; to feel; to experience?

    There’s little point in exploring space if one know how this universe works. One knows the rules, knows all the ways it can play out, and there’s no surprise waiting on the other end of any venture one can imagine embarking on.

    That’s my theory. The Great Filter is just depressive boredom. We don’t see other life because by the time a civilisation is able and ready to spend thousands of years travelling through deep space, they’ll have already lost any motivation they might have had to do so.

    I suspect that there’s at best a very short window wherein a species is both knowledgeable enough to dream of space exploration and technologically capable of sending any significant amount of artificial constructions out there.

    Not to mention that anything an alien species might send into interstellar space is unimaginably unlikely to be recorded exactly at precisely the moment they pass another lump of matter - especially if the window is as short as I fear.


  • This comment tells me that you do not fully understand reversible computing, thermodynamics, nor what I am trying to say. The snark does not motivate me to be patient or pedagogical, but I’ll still give it a shot.

    By interfering with a closed system as an entity outside of that system (for example by extracting information by performing a measurement on any of its component subsystems such as the position or momentum of a particle), you are introducing a dependency of that formerly closed system’s state on your state and that of your environment. Now, by state I mean quantum state, and by interfering I mean entangling yourself (and your environment) with the system, because our reality is fundamentally quantum.

    Entanglement between an observer and a system is what makes it appear to the observer as if the wave function of the system collapsed to a (more) definite state, because the observer never experiences the branching out of its own quantum state as the wave function of the now combined system describes a superposition of all possible state combinations (their (and their environment’s) preceding state × the system’s preceding state × the state of whatever catalyst joined them together). The reason an observer doesn’t ever experience “branching out” is because the branches are causally disconnected, and so each branch describes a separate reality with all other realities becoming forever inaccessible. This inaccessibility entails a loss of information, and this loss of information is irreversible.

    So there you have it. You can never extract useful work from a closed system without losing something in the process. This something is usually called “heat”, but what is lost is not merely “heat”: it is the potential usefulness of the thing of interest. But it really all boils down to information. Entropy increases as information is lost, and this is all relative to an observer. Heat dissipation represents “useless information” or “loss of useful/extractable energy” as it concerns an entity embedded in a quantum wave function.



  • A partial answer to your question is that there’s a minimum amount of heat necessarily radiated when doing computation, given by the Landauer principle.

    Furthermore, I also do not think that we will detect dyson spheres, because if a civilisation wishes to hide, they won’t radiate heat uncontrollably by extracting all possible energy, but rather send that energy elsewhere, for example by dumping it into a black hole. But I could be wrong and such a civilisation might care more about energy than remaining undiscovered.



  • As I understand it, they are making measurements of an otherwise single isolated particle as it moves about in a controlled space, and the measurements confirm (yet again) that the measurement outcomes match the probabilities given by the Schrödinger equation, which means that it interferes with itself.

    The language used may lead some to think that we now have images showing a wave-like particle, but again, that’s not something that can ever happen. What we have are boring old images of a single classical-looking particle, but the patterns they display tells us that quantum mechanics is very much at play in between the takes.



  • tl;dr:

    Peter Schauss at the University of Virginia says the wave packet is such a well-understood component of quantum theory that the findings of the new experiment are not surprising – but they do show that the researchers had a high degree of control over the processes used to cool and then precisely image the atoms.

    I’m not entirely sure what they mean by having images of their waviness, because that is not how it works. You can not measure a quantum wave, because it isn’t a “particle” wave but a wave-like distribution of mutually exclusive measurement outcomes. Taking a picture is the same as entangling yourself, which embeds you in the quantum wave function such that it describes all possible combinations of you ending up with every possible outcome.