Jump to content


Senior Members
  • Content Count

  • Joined

  • Last visited

  • Days Won


Posts posted by uncool

  1. It's worth noting that the Schrodinger equation isn't really a single system. It's a family of systems. Some simple examples have been solved (as noted); some more complex ones have been numerically approximated by perturbation theory.

    So the question doesn't quite make sense; it's kind of like asking "Has A + B = C been solved?"

  2. 8 hours ago, MigL said:

    As I said to Phi, quote where Essereio states that black Americans are less than human.
    He made some points about certain groups being loud and obnoxious, and that is certainly true, about blacks, whites, indigenous, etc.
    One could say the protesters are loud and obnoxious, and they were composed of many different ethnic groups.
    And he made the point about A Hitler trying to do good...:doh:

    Generally speaking, I am on your side. In this specific case, they made a comment where it is difficult to interpret it in any way that isn't racist:


     Hitler wanted good for people. It's just that his actions were incorrect towards taking out the trash(religion).

    The first part of this comment implies that the people that Hitler deliberately committed genocide against don't get to count as "people". The second part is so facially false in its misrepresentation of basic history that it indicates the writer is either a troll or such a committed racist that they don't even care about the genocide itself. Either way, a forum setting is not going to convince them to change their ways.

    1 hour ago, MigL said:

    So now I have made the almost exact same arguments that Essereio made ( other than the A Hitler comments ).
    I have not gotten any neg reps, been called racist, or been banned.
    What is the difference ?

    Part of the difference is that they did more than express distaste. They used that distaste to make derogatory claims about black culture as a whole, and to dismiss the protests without even engaging with the basic claims of the protests, with a strong implication that black people don't deserve to protest.

    On a  side note:

    5 hours ago, MigL said:

    Do you like rap music and the 'gangsta' culture, and disrespect for authority, it promotes ?

    I strongly disagree with the implication that "disrespect for authority" is necessarily a problem. To a large extent, the protests are about the claim that that authority is being abused - and authority being abused should not be respected.

  3. 25 minutes ago, Jack Jectivus said:

    The optimal AI would be built sooner if it was designed to punish

    True - or if it could credibly threaten to punish. And in this "theory", the way to credibly threaten is to always follow through on threats. To not have to update - even when that update is being created.

    Basically, you seem to be trying to analyze from the moment of the AI's creation, as if that is set in stone. In this "theory", that is an error. Instead, analyze which class of AI gets to optimization sooner - one that credibly makes the threat by committing to following through, and therefore may convince people to contribute to creating it earlier, or one that doesn't.

  4. Again: if people of the past can't guess whether punishment would be carried out, then the threat fails to motivate them. Which means that an AI that wants to be created (and which also subscribes to updateless decision theory) would prefer to be in the class of AI that made and carried out that threat, according to this theory.

  5. Sorry if I'm insisting a bit much, but you have missed the point of updateless decision theory. If the AI doesn't plan to carry out its threat, then it fails as a threat.

    Have you read Yudkowsky's answer to Newcomb's paradox? Because your critique is a lot like the answer of "Why don't I plan to take one box, then change my mind and take both?" If you don't accept his argument there, then you are undermining one of the foundational assumptions behind the basilisk.

    Note: I am not saying that you are necessarily wrong to reject the argument; however, if you do so, it doesn't really make sense to talk about something that depends so heavily on that argument.

  6. 1 hour ago, Jack Jectivus said:

    My critique is more about the error in supposing that an AI would punish people for their actions when it's goal is optimization. It is true that it may acausally promote its own creation, but punishing people after it has already been built would be illogical, supposing that it's goal is optimization.

    Not if committing to the punishment is how it acausally promotes its creation. Which is part of the point of "updateless decision theory".

  7. 23 hours ago, Jack Jectivus said:

         Roko's Basilisk is a famous thought experiment

    Not especially famous, no. It's a niche thought experiment from LessWrong.

    And your post takes it out of its specific context, namely, as a thought experiment about the effects of Eliezer Yudkowsky's "updateless decision theory" and "acausal trade".

    Note: I'm not saying that any of the above named things are correct or make sense, but your post ignores the foundation on which the thought experiment is based.

  8. 3 hours ago, AbstractDreamer said:

    Why is it apparent that small things determine how big things work and not vice versa?

    Because big things are made of small things. Alternatively: because large spaces can be broken down to small spaces, in a way that respects the laws of physics.

    A little more technically, because the laws of physics are local. They are differential equations where all derivatives of things at a point are determined by values of those things at the same point.

    "Why" for that can be explained by relativity: things can only be affected by what has happened within the past light-cone, which is necessarily small when time is short.

  9. 13 hours ago, DimaMazin said:

    What is exact  sin(Pi/4)=21/2/2 or  sin(Pi/4)=0.7071067812 ?   Can you define sine of any angle with exponents?

    Depends on what you mean. For any angle A, sin(A) = (e^(i*A) - e^(-i*A))/2i, which is an expression of the sine using exponents, but I'm guessing that's not what you're going for (in part, because you seem to have an objection to numerically finding the value).

    It sounds like you are trying to define sines in terms of radicals of rational numbers. There are uncountably many angles, and only countably many expressions using radicals. So we'd have to restrict ourselves to some countable subset of angles.

    You chose to look at pi/4; that suggests using only rational multiples of pi. And with that restriction, the answer is yes - sin(pi*(a/b)) can always be expressed in terms of radicals. In fact, the expression I gave above can count: sin(pi*(a/b)) = (1^(a/2b) - 1^(-a/2b))/(2*(-1^(1/2))).

    That expression...isn't really helpful in finding the value of sin, but I'm pretty sure it can be converted to an expression that is.

  10. On 2/1/2020 at 2:32 PM, geordief said:

    Well I have come across the geometrical representation of the Tangent space as a kind of group of all the vectors at a point of a Surface that are tangential to the surface

    Visually they look  a bicycle wheel with very many spokes lying flat on the surface with the centre of the wheel situated at the point on the surface


    Now ,the Cotangent Planes I view visually as an open book with many,many pages and with the spine of the book following a direction that is perpendicular to the point on the surface of the surface.


    So I picture the first plane (the Tangent plane) as geometrically perpendicular to the Cotangent Planes


    I see them as very similar but mutually perpendicular.


    Have I got a correct picture of the Cotangent plane(s)?

    I think you are thinking of "normal vectors", which are not cotangent vectors, no. For one thing, normal vectors depend on how you have embedded your manifold into a larger Euclidean space, whereas tangent and cotangent vectors do not. 

  11. 12 minutes ago, Markus Hanke said:

    But one could still say that they are locally diffeomorphic, right?

    Yes (even better: that the map is a local diffeomorphism; the difference being whether there is *some* map or whether it is *this* map), but that is a very weak statement; any two smooth manifolds of the same dimension are locally diffeomorphic - because locally, the differential topology is that of Euclidean n-dimensional space. The term I think you want is that they are locally isometric (or more specifically, that the "wrapping map" is a local isometry), that is, that the metric, or the geometry, matches.


    4 hours ago, Markus Hanke said:

    Why does this not apply to the cylinder and flat sheet example?

    Because the map is not invertible - only locally invertible. When you wrap the sheet around the cylinder, it will cover itself (infinitely many times, even). 

    Also, "diffeomorphism" is a term properly from differential topology - the metric plays no role in it (e.g. a "smoothed" coffee cup is diffeomorphic to a donut). The term "isometry" is much stronger - literally "same metric". 

  13. 55 minutes ago, Markus Hanke said:

    The metrics are not the same, but they are diffeomorphisms of one another.

    I think you mean the opposite: the spaces are not diffeomorphic, but they are locally isometric

  14. 11 minutes ago, Conjurer said:

    You are missing the logic behind finding the limit.  When you take a limit you are discovering what the value would be when it actually is zero by looking where it approaches on a graph.  Then you don't have to graph it to see this every time.  

    You are missing the logic behind the idea of taking limits, which is to avoid actually dividing by zero. The fact that you seem to think that the process is "magical" is a strong indicator of why. 

  15. 1 minute ago, Conjurer said:

    My bad, then the answer to the derivative of that would be zero.

    you're missing the point taeto is making. 

    Let me put it quite simply: no, the process of taking the derivative never involves a division by 0. Period. 

  16. 1 minute ago, Conjurer said:

    The equation y = 1 or y = constant is excluded from this working.  It is a vertical line, so it fails the vertical line test, and it is not a function.  It has to be a function.

    ...y = 1 is a horizontal line, not a vertical one; f(x) = 1 is a function. 

  17. 7 minutes ago, Conjurer said:

    All you have to do is cancel out the change in x on the bottom with the change in x on the top in the equation of the derivative.  It doesn't matter if the change in x is zero.

    ...yes, it does. The definition of the limit of a function specifically excludes the value of the function of the limiting value from being relevant.

    "For all epsilon greater than 0, there exists a delta greater than 0 such that for any 0 < |x - a| < delta, |f(x) - L| < epsilon"


  18. 6 minutes ago, Conjurer said:

    I already explained this, and it is described in the video.

    Please point out where you explained any actual division by 0, which is the specific distinction taeto is making.

    7 minutes ago, Conjurer said:

    Khan academy is now an accredited university.

    ...no, it isn't. 

  19. 25 minutes ago, Conjurer said:

    I guess you didn't watch the video and you are unwilling to learn.  The video describes how you can divide where the change in x and y becomes zero.  The equation for the derivative is the same equation they use in hyperreals.    

    Except in neither case is there any actual division by 0.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.