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Cake day: September 6th, 2024

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  • WoodScientist@lemmy.worldtoAsklemmy@lemmy.mlWhy would'nt this work?
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    4 months ago

    It would work, but only in the impossible world where you have a perfectly rigid unbreakable stick. But such an object cannot exist in this universe.

    Pick up a solid rigid object near you. Anything will do, a coffee cup, a comb, a water bottle, anything. Pick it up from the top and lift it vertically. Observe it.

    It seems as though the whole object moves instantaneously, does it not? It seems that the bottom of the object starts moving at the exact same instant as the top. But it is actually not the case. Every material has a certain elasticity to it. Everything deforms slightly under the tiniest of forces. Even a solid titanium rod deforms a little bit from the weight of a feather placed upon it. And this lack of perfect rigidity means that there is a very, very slight delay from when you start lifting the top of the object to when the bottom of it starts moving.

    For small objects that you can manipulate with your hands, this delay is imperceptible to your senses. But if you observed an object being lifted with very precise scientific equipment, you could actually measure this delay. Motion can only transfer through objects at a finite speed. Specifically, it can only move at the speed of sound through the material. Your perfectly rigid object would have an infinite speed of sound within it. So yes, it would instantly transfer that motion. But with any real material, the delay wouldn’t just be noticeable, but comically large.

    Imagine this stick were made of steel. The speed of sound in steel is about 5120 m/s. The distance to the Moon is about 400,000 km. Converting and dividing shows that it would actually take about 22 hours for a pulse like that to travel through a steel pole that long. (Ignoring how the steel pole would be supported.)

    So in fact, you are both right and wrong. You are correct for the object you describe. A perfectly rigid object would be usable as a tool of FTL communication. But such an object simply cannot exist in this universe.










  • Exactly. Their ONLY virtue is convenience. Either you’re there for a prescription and buy something because you’re already there, or you’re just looking to do a quick stop. They’re basically a glorified convenience store that happens to have a pharmacy attached. Their prices are high, but they do have convenience on their side. You don’t have to walk across half a mile of parking before getting to the front door. You don’t have to walk into a giant warehouse store that corrals you into shopping in a giant counterclockwise loop. Walgreens does have the convenience option over shopping at a big grocery store.

    And this is what is so bone-headed about these locking cases. Again, their ONLY advantage is convenience. If they’re going to slow things down by putting a bunch of barriers between me and the things I want, I might as well just spend the same amount of time, go to the full-sized grocery store, and save some money.



  • Because it’s clearly being banned, not because of privacy violations, not because of the nefarious impact of a foreign government, but because of the content that is shared on it. It is the only major social media platform with a strong pro-Palestinian viewpoint on it. And the people in Congress have been caught on camera explicitly stating this is why they want to ban it.

    I hate Tiktok. I don’t use it. Never have. But I still don’t want to see the US turn its internet into the Great Firewall of China 2.0.

    The leaders in Congress cannot stand the idea of there being a social media platform that is popular in the US that isn’t hosted in the US. Why? The answer is simple - control. All the US social media platforms are heavily influenced by the US government. Hell, most of them openly contract with the NSA. Facebook is an NSA contractor. These platforms get a ton of money from the US government. And despite what conservatives bitch at in regards to “being censored,” the real censorship is against anything that doesn’t advance US power and influence. Outside of Tiktok, the major platforms heavily censor pro-Palestinian messages and stories. Go to r/worldnews and post anything other than “Palestinians deserve to be vaporized,” and you’ll be banned within 5 minutes. It’s literally that bad. Even when outright bans aren’t in place, the platforms will severely down shift any pro-Palestinian content and keep it out of peoples’ feeds.

    “Beware of he would would deny you access to information, for in his heart, he dreams himself your master.”






  • You know what. Fuck it. Let’s make the world more interesting. Let’s legalize consensual cannibalism! We’ll regulate it like assisted suicide, so there are safeguards in place to prevent exploitation and such. And you won’t be able to pay someone (or their loved ones) in order to let you cannibalize them. But if everyone involved is of sound mind, if there’s plenty of time to change your mind, and no one is getting paid or coerced? Have at it! I believe in freedom so much, that if you want to willingly let a cannibal kill and eat you, by God, that should be your right! Let us legalize consensual cannibalism!



  • Yes, you recognize the fact, but you haven’t internalized its implications. You can only have a universal present in a universe of shared time. Ultimately, “the present” is something applicable to and that exists within the mind of a single observer.

    One of the hallmarks of science is that different people can independently measure something and confirm its existence. If no two observers can ever agree on what constitutes “the present,” then how can “the present” be said to exist at all? It’s a fundamentally unscientific concept.


  • You’re still imagining that there is some fixed universe playing out at constant time, and that we all just experience the echoes of this present in different orders. This isn’t what relativity says. Clocks traveling near the speed of light don’t just appear to slow down, they actually slow down.

    Different regions of the universe don’t even experience the same flow rate of time. Someone living on a mountaintop experiences time faster than someone at sea level. And yet you cling to this fantasy of their being some universal “present.” You cannot have a universal present in a universe composed of different flow rates of time!


  • https://en.wikipedia.org/wiki/Relativity_of_simultaneity

    The present does not exist. From the previous link:

    It can be argued that special relativity eliminates the concept of absolute simultaneity and a universal present: according to the relativity of simultaneity, observers in different frames of reference can have different measurements of whether a given pair of events happened at the same time or at different times, with there being no physical basis for preferring one frame’s judgments over those of another. However, there are events that may be non-simultaneous in all frames of reference: when one event is within the light cone of another—its causal past or causal future—then observers in all frames of reference show that one event preceded the other. The causal past and causal future are consistent within all frames of reference, but any other time is “elsewhere”, and within it there is no present, past, or future. There is no physical basis for a set of events that represents the present.

    Many philosophers have argued that relativity implies eternalism.[6] Philosopher of science Dean Rickles says that, "the consensus among philosophers seems to be that special and general relativity are incompatible with presentism.

    If two observers will disagree on which events happened in “the present,” then “the present” cannot exist as a real universal entity. “The present” only makes any physical sense in classical, pre-20th century Newtonian mechanics.

    This is why the block universe or eternalism makes more sense.