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Joined 1 year ago
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Cake day: June 30th, 2023

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  • Drives connected to usb have an unstable connection in my experience, this is very annoying and gets worse with hubs.


    RAIDs reduce the time a system is offline and reduce data loss, if a drive fails and you can afford to wait for the new disk and the backup to restore, and have regular backups that ensure no important data gets lost (though remember the data added between backups may be lost) then you don’t need a RAID.

    I don’t use RAIDs cause if my disk fails then I can stomach the 2-4 days it takes to buy a new one and restore the backup

    Very important: use S.M.A.R.T and a filesystem with checksums to make sure you’re not backing up corrupted data and know to get a new one


    For encryption at rest you may want to look at clevis and tang, though you need a server in your home network for this to work. The client (with clevis) then decrypts the disk at boot if it can reach the server (tang). The server can’t decrypt the data without the client secret and the client can’t decrypt it without the server public key.

    Don’t know what your server could be though, maybe a router with custom firmware?


    You should also look into cloud storage/rclone, that way you can automate your backups more and reduce the need for manual intervention.

    I use rclone and restic to automatically backup my servers daily which takes a few seconds most of the time due to them being incremental backups.




  • Well, yes. We don’t know if the measurement we take is the result of a wave form collapse (we caused it) or the result of someone else having measured it, which would giving us the oposite value that they measured. We can’t tell if someone “sent” information or if it was the random result and we have no way to chose what value we (or the other end) gets when we collapse it.

    This isn’t easy to explain over text so I’d recommend watching this video, specifically chapter “How to exploit?” as the visuals make it easier to understand.


  • Basically as far as we can tell there there is no information traveling at FTL speed so it just works? All information that is traveling is just as fast as c or slower.

    “Certain phenomena in quantum mechanics, such as quantum entanglement, might give the superficial impression of allowing communication of information faster than light. According to the no-communication theorem these phenomena do not allow true communication; they only let two observers in different locations see the same system simultaneously, without any way of controlling what either sees.” link

    “In physics, the no-communication theorem or no-signaling principle is a no-go theorem from quantum information theory which states that, during measurement of an entangled quantum state, it is not possible for one observer, by making a measurement of a subsystem of the total state, to communicate information to another observer.” link


  • According to special relativity, the energy of an object with rest mass m and speed v is given by γmc2, where γ is the Lorentz factor defined above^1. […] The γ factor approaches infinity as v approaches c, and it would take an infinite amount of energy to accelerate an object with mass to the speed of light. The speed of light is the upper limit for the speeds of objects with positive rest mass[…] This is experimentally established in many tests of relativistic energy and momentum.

    More generally, it is impossible for signals or energy to travel faster than c. One argument for this follows from the counter-intuitive implication of special relativity known as the relativity of simultaneity. If the spatial distance between two events A and B is greater than the time interval between them multiplied by c then there are frames of reference in which A precedes B, others in which B precedes A, and others in which they are simultaneous. As a result, if something were travelling faster than c relative to an inertial frame of reference, it would be travelling backwards in time relative to another frame, and causality would be violated. In such a frame of reference, an “effect” could be observed before its “cause”. Such a violation of causality has never been recorded, and would lead to paradoxes such as the tachyonic antitelephone.

    More info here

    1 γ = (1 − v2/c2)−1/2