Jump to content
• Sign Up

# Leaderboard

1. ## Prometheus

Senior Members

3

1647

Moderators

3

25528

3. ## Markus Hanke

Resident Experts

2

897

4. ## Ghideon

Senior Members

2

1499

## Popular Content

Showing content with the highest reputation on 01/22/20 in all areas

1. 3 points

## men vs woman

While female and male brains have differences, it would be difficult to pick apart what is truly biological variance between populations and what is cultural conditioning. I vaguely recall a study that found female hippocampi were on average smaller than in males, which was said to explain why men were better navigators. But we also know parts of the brain less used will atrophy. So is it a case of their hippocampi being intrinsically smaller, or a result of gender roles directing its use (or lack of)? When women have risen to prominent historical roles they have pretty much done as men have done - Wu Zetian, Boudicca, Hypatia (but maybe that's because they emerged in patriarchies). There is also evidence of early societies that while not matriarchal, were more balanced. The Spartans are a probably the best documented example, and weren't significantly different from surrounding societies. I've also heard it said men more readily pursue risky pursuits, perhaps leading to voyages such as Colombus'. Assuming this is a neurobiological difference, it wouldn't necessarily preclude risky behaviour from men. Remember Colombus was sponsored by both Queen Isabella and King Ferdinand, with the former willing to sell some jewels to fund it (thoough she didn't need to). War would still be conducted by men on the field; aside from differences in physiology making men on average more suited to those demands, sending women to fight would be a flawed strategy. The Romans lost ~300,000 men to Hannibal in the Punic wars from a total population of ~3.5 million - thats a huge proportion. If they had all been women of child-bearing potential Rome would almost certainly have fallen. Overall i don't think there'd be gross changes to the patterns of war, economic cycles, spiritual practices, technological development etc - just a lot of changed details which are impossible to guess at. They say men are from Mars and women from Venus, but we all know they're both from Earth.
2. 2 points

## Banned/Suspended Users

conjurer suspend for a week for persistently posting above his level of understanding
3. 1 point

## I need help with my math problem.

I think I made an error in the rotation, applying the wrong matrix at A and B,D. I'll post an update once i get some time. It does not affect my conclusion, but it affects the signs in the final matrices.
4. 1 point

## Left hand right hand?

The mass has been removed☺️ Occasionally it feels as if my head has been removed the pain suggest otherwise not to mention that using my cell phone finding my head is not that difficult somewhat ugly but not difficult to do. the fact that I am using my cell phone and am not just sitting here staring at it wondering what to do next in my opinion suggests good days to come. they were gonna give me another 3 months before the procedure but had to move it up. Doing well.
5. 1 point

## Comments on Moderation

A recent suspension was announced for "persistently posting above his level of understanding" and I want to clarify that it's not against the rules to be wrong, but it is against the rules to not back up claims. If you're going to assert that the moon is made of cheese, you're going to have to back that up. This requirement is explicitly pointed out in the speculations guidelines. The underlying rules violation is soapboxing: repeated claims without justification for them. Further, making multiple wild assertions not based in any mainstream science can be considered spamming. Both behaviors are unacceptable.
6. 1 point

## Rare off-Earth elements

There should be abundant carbonaceous chondrite materials in asteroids that could be a raw material for making polymers. Given carbonaceous meteorites can have significant amounts of nickel-iron - mixed in as grains or chondrules - as well as oxides and sulphides, they have hypothetical potential for asteroid mining
7. 1 point

## General Relativity Explained

Under certain circumstances you can use either one to describe the same thing, but that is not always the case. As a counterexample, consider the (2D) surface of a (3D) cylinder - it is extrinsically curved, but intrinsically flat. So clearly, in this case these two descriptions are not equivalent. In the case of GR, spacetime is not thought to be embedded into any higher dimensional space, so it has only intrinsic curvature. For arguments sake, it is possible to construct a mathematical model that embeds spacetime into something higher-dimensional, and then use extrinsic curvature to capture all the same information. The problem with this is that the embedding would have to have a lot of dimensions; I can’t actually remember the exact number, but I think it was 48. So I fail to really see the advantages in this, as it makes most of the maths very much more complicated than it already is in standard GR. In general terms, any Riemann manifold can be embedded into a higher-dimensional Euclidean space in such a way that paths lengths are preserved. This is called the Nash embedding theorem.
8. 1 point

## Impeachment Hearings

You auto have known better...
9. 1 point

## Impeachment Hearings

Sure I just wanted to make sure that "agreed" has very different meanings in the two procedures plus the fact that the talking point as a whole (i.e. everything is following the Clinton precedent) is inaccurate, as I think it is quite important context.
10. 1 point

## I need help with my math problem.

Ok! Here are some quick calculations regarding the original question. NOTE: I’ll handle this as a mathematics problem only. I do intentionally not mention any electromagnetics since there is not enough information provided to know if this setup have any physical meaning or is physically possible. I’ll write out conclusions made from the notes above to give the whole picture, maybe unnecessary detailed. It’s a little tricky to read all the indexes in the original image but the intention is to keep the numbering and letters from other pictures posted so far. Let’s start with an equilateral triangle ABD. ABD is placed in a cartesian coordinate system xy. Initially there is no need for a z-axis. The corners are associated with vectors and the vectors have x and y components identified by subscript. Since ABD is equilateral and the vectors having identical length that lead to some symmetries and one zero component. $B_{4x}=B_{5x}\\B_{4y}=-B_{5y}\\B_{6y}=0$ At each point A,B,D, add* the pair of vectors associated with that point. Use symmetries to simplify: $A: B_{1}=\begin{bmatrix}B_{4x}\\B_{4y}\end{bmatrix} +\begin{bmatrix}B_{5x}\\B_{5y}\end{bmatrix}=\begin{bmatrix}B_{4x}+B_{5x}\\B_{4y}+B_{5y}\end{bmatrix} =\begin{bmatrix}2B_{4x}\\0\end{bmatrix}$ $B: B_{2}=\begin{bmatrix}B_{5x}\\B_{5y}\end{bmatrix}+\begin{bmatrix}B_{6x}\\B_{6y}\end{bmatrix}=\begin{bmatrix}B_{5x}+B_{6x}\\B_{5y}+B_{6y}\end{bmatrix} =\begin{bmatrix}B_{4x}+B_{6x}\\-B_{4y}\end{bmatrix}$ D:$B_{3}=\begin{bmatrix}B_{6x}\\B_{6y}\end{bmatrix}+\begin{bmatrix}B_{4x}\\B_{4y}\end{bmatrix}=\begin{bmatrix}B_{6x}+B_{4x}\\B_{6y}+B_{4y}\end{bmatrix} =\begin{bmatrix}B_{6x}+B_{4x}\\B_{4y}\end{bmatrix}$ These directions seems to match the hand-drawn picture by OP. To check how “force” vectors “F” would look like, we apply rotation** by 90 degrees ccw by using matrix $\begin{bmatrix}0&-1\\1&0\end{bmatrix}$ at point B and D. At point A we apply 270 degrees of rotation** to match original picture. $\begin{bmatrix}0&1\\-1&0\end{bmatrix}$ $A: F_{1}=\begin{bmatrix}0&-1\\1&0\end{bmatrix} \cdot \begin{bmatrix}2B_{4x}\\0\end{bmatrix} = \begin{bmatrix}0\\2B_{4x}\end{bmatrix}$ $B: F_{2}=\begin{bmatrix}0&1\\-1&0\end{bmatrix} \cdot \begin{bmatrix}B_{4x}+B_{6x}\\-B_{4y}\end{bmatrix} =\begin{bmatrix}-B_{4y}\\-B_{4x}-B_{6x}\end{bmatrix}$ $D : F_{3}=\begin{bmatrix}0&1\\-1&0\end{bmatrix} \cdot \begin{bmatrix}B_{6x}+B_{4x}\\B_{4y}\end{bmatrix} =\begin{bmatrix}B_{4y}\\-B_{6x}-B_{4x}\end{bmatrix}$ Result is vector F1 in y direction at A and vectors F2 and F3 pointing inwards into the triangle at points B and D. This seems to match the directions of "F" vectors in OP's picture. Due to symmetry the x-components at B and D cancels. So the total sum of F1,F2 and F3 is in y direction. Note again: this is a set of vector calculations. It could possibly represent some setup of magnetic fields, currents and forces. But so far the thread lacks the responses to address that possibility. *) If this would have been magnetic fields, they add as vectors. **) If there would have been currents, right hand rule tells vector directions.
11. 1 point

## Limits

! Moderator Note You have already demonstrated very well that you don’t know what you are talking about. I don’t think you need to start a new thread to provide more evidence.
12. 1 point

## The speed of propagation of gravity

No, it just means that they weren’t emitted simultaneously - which is what one would expect, since these two forms of radiation are the result of different physical processes. This is inconsistent with the basic principles of GR, as well as with the specific mathematics of gravitational waves. The opposite is in fact the case - since the dynamics of gravitational waves are non-linear (unlike e.g. EM waves), they interact both with other gravitational waves as well as with themselves. In this manner you get a number of effects that are exclusive to gravitational waves, and some of these actually propagate slower than the speed of light (specifically so-called “wave tails”). However, a free wave in otherwise empty space must propagate at exactly c.
13. 1 point

## Energy for splitting seawater ?

IIRC electrolysis is ~1.25 eV, so it would be 7.5 x 10^26 eV for a kg. That’s 120 MJ, or 33.3 kWh
14. -1 points

## Promoting murder with neurological manipulation .

They offered me a job doing this and learned me how to do neurological modulation and read specialist code . I have a bank transfer receipt that proves the link .
×

• #### Activity

• Leaderboard
×
• 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.