1

Technology / Re: Can you give AI emotions?

« on: 19/11/2016 14:38:04 »

AI can be programed to understand emotions and thats all thats necessary.

2

General Science / Re: Could humanity survive a nuclear war?

« on: 16/11/2016 23:50:19 »

I was married to the same woman for 26 years and loved her more each day. If she were still alive, I'm pretty sure we'd be planning our next joint mission. On the other hand when I fly with a male buddy, we reckon 2 - 4 weeks is the safe limit for an expedition, even though we operate very efficiently together.

Crew compatibility is very important. In a small crew there's a significant difference in dynamics between even and odd numbers, and the boundary between gelling and grating is very hard to predict. I think that the sexual instinct is so deeply ingrained that a male/female pair is more likely to remain functional as a team than two of a kind, though I'm open to evidence from homosexual pairs.

Shackleton's exploits show the most extreme examples of cooperation under stress in a fairly large all-male team. However Shackleton's crew did have a banjo, seemingly inexhaustible supplies of tobacco, and occasional encounters with edible penguins and seals. The lack of such distractions on Mars suggests that a friend of the opposite sex might be a good idea, and I promise not to smoke or play the banjo. 

3

Physics, Astronomy & Cosmology / Re: Could the big bang be in an infinite repeating cycle?

« on: 15/11/2016 18:02:40 »

When speculating about the so-called "Big Crunch", I think it is a mistake to assume that the cosmos is finite to begin with. If instead, the cosmos is infinite and our observed Big Bang is really only a local "White hole" event, then maybe we can start speculating about what the mass limit might be for black holes.

Just consider the possibility that if the cosmos is in fact infinite, other big bangs may be occurring all the time but are too far outside our observational parameter. Maybe the truth is: Our "Big Bang" really isn't all that big when one considers the possibility of an infinite cosmos.

4

Technology / Re: Can you give AI emotions?

« on: 14/11/2016 23:57:56 »

Problem one, you have to quantify emotion. Now in living species my opinion is it is altered states as a result of chemical inducement, adrenal glands or whatever. Could emotional responses be programmed after observation, certainly. So now we program the computer to respond the same as a person reacting to say being put in a situation   where fight or flight kicks in. It is like a chess game, you analize your options or not and react. So when is it called an emotion?

It certainly has to do with the epiphenomenon we call consciousness, but if replicated by say an ai computer, it would not be consciousness, thus emotionless. But if we are wired to react on emotions, and a computer is programmed to emulate thee emotions, how do you know the difference?

5

The Environment / Re: Do street lights waste energy unnecessarily?

« on: 14/11/2016 19:22:52 »

Alas, passenger jets generally fly too high to ingest many insects, and flying bugs just clog up the air intake of a piston engine without enriching the fuel burn. That's where millions of years of bat evolution  beat a hundred years of human thought: the bat can ingest, process, eliminate the waste, convert the protein into muscle (engine maintenance in flight!) and the fat into fuel, whilst doing all sorts of aerobatics and courting a mate, in pitch darkness, then settle down and make baby bats. The best I can manage after a night flight is to fall asleep in a taxi. 

6

Physics, Astronomy & Cosmology / Re: If a hole were drilled through Earth and you jumped through, how would you exit?

« on: 08/11/2016 20:00:08 »

bore through the Earth's crust and find out what's actually down there

There was an attempt to do this, in the 1960s: The Mohole Project.
They made the task easier by drilling in deep ocean, where the crust is thinner.

See: https://en.wikipedia.org/wiki/Project_Mohole

Or you could just go to a place where the layer beneath Earth's crust comes up to the surface, as it does in Iceland.
Iceland is a part of the mid-Atlantic ridge that happens to be above sea-level. New crust is actively forming there.

Perhaps 20 or 30 kilometers down, there might be vast reserves of planetary methane gas, as some theorists have speculated.

Technically, drilling in deep water is quite difficult.
And natural gas behaves quite differently under extreme pressures.
In the movie "Deep Horizon", they illustrated, but didn't attempt explain that under extreme pressures, water and methane form a clathrate "snow" that gummed up all their pipes, and prevented their safety equipment from operating.
Indeed, it is thought that there are considerable deposits of clathrates around the world, which could potentially be mined for natural gas (provided that oceanic warming doesn't melt them first).

7

General Science / Re: Is there any scientific evidence for an afterlife?

« on: 08/11/2016 11:03:57 »

There are some clues suggesting there is no life after death. It is actually about the consciousness because that is what we are interested in. When there is slight a brain damage or a neuronal malfunction the person consciousness seems to be affected, sometimes it doesn't semm to be the same person anymore. I think consciousnesses can be gradually lost.
Also, when sensors information is lost, like, vision, touch etc, the person eventually would not be able to distinguish between dream an reality. Hypothetically a consciousness as a separate entity without receiving any input from the outside world (through sensors) it will probably go crazy. All memories would fade away in time, until everything dissapears. It would be the worst nightmare.

I don't see any way of full consciousness to survive without a brain. I think all organs functions and all sensors are required to create a complete consciousness. Even if the consciousness survives as an entity (which is impossible) it will alter significantly.

The  consciousness somehow like a program in a computer. The program can't run if you power the computer off. Technically the neurons send signals to each other. If you destroy the neurological network the signals dissapear.
These are only, non specialist, personal opinions.

8

Physics, Astronomy & Cosmology / Re: What is the force exerted by the sun on the earth

« on: 08/11/2016 09:41:37 »

You seem to imply that (GPS satellites) in a "frame of reference" which consists only of the satellites, and the Earth.

GPS has 6 satellites chasing each other around a circular orbit. This means:
- Constant distance from the center of the Earth = constant depth in the Earth's gravitational well (about 20,000km).
- Constant orbital velocity around the Earth
- Constant relativistic time correction applied to each of the satellites
- Each of these 6 satellites is in the same frame of reference

However, the surface of the Earth:
- Is at a different depth in the Earth's gravitational well (about 6,370km)
- Is moving at a very different velocity
- And so the surface of the Earth is not in the same frame of reference as the satellites.

To get global coverage, additional satellites are placed in additional circular orbits, in 6 planes relative to the Earth's axis
- Because these planes are angled relative to each other, the satellites in different planes are in different frames of reference from each other.

their "primary mission" to keep time, and broadcast it to GPS receivers on Earth

So although the satellites are in a different frame of reference from the surface of the Earth, their time signals are preconfigured to be received with accurate time by GPS users on Earth's surface (or users in aeroplanes or Low Earth Orbit who are keeping Earth time).

can be accomplished without regard to any influences outside this "frame". I mean, aren't the satellites influenced by external gravitational "tugs" from the Moon, and the Sun?

Yes, the Sun and Moon and Earth's non-spherical shape do exert tugs on the satellites, which slowly distorts their orbits. This is why the orbit data transmitted by the satellites is typically updated about every 4 hours, so receivers on the ground know the precise orbit of every satellite.
- The Sun is 150 million km away, so it affects every satellite equally
- The Moon is much closer - at about 380,000km, it is 19 times farther away than the GPS satellites. But it has 1.2% of the mass of the Earth. Apply an inverse square law, and that is a very small perturbation in the gravitational well.

Shouldn't these "tugs" be taken into account, when the satellites broadcast their signals to Earth.

The Earth is at the same average distance from the Sun and the Moon as are the GPS satellites.
The Earth is in "free fall" around the Sun and the Earth/Moon center of gravity, as are the GPS satellites.
So I expect that these small tugs/relativistic corrections will average out over a 24 hour period.

9

General Science / Re: Is there any scientific evidence for an afterlife?

« on: 07/11/2016 23:33:18 »

I agree with Ethos that everyone has a right to their beliefs. However, many publications have certain rules (as is their right) which must be adhered to before publication is approved. I'm sure that if the believers you mention are able to provide experimental proof which meets that required by drug testing - standards of trial design, testing and data analysis  - then I'm sure you would agree that their results should be published. Belief rarely meets such standards.

10

That CAN'T be true! / Re: Could a person write two different exam answers, one with each hand?

« on: 07/11/2016 22:20:47 »

Two brains can do two things at the same time ...

https://www.youtube.com/watch?v=wfYbgdo8e-8

11

That CAN'T be true! / Re: Could a person write two different exam answers, one with each hand?

« on: 06/11/2016 20:56:45 »

Well zx16. the more complicated the question, the greater ones uncertainty of the answer being correct, you have to know how to formulate the question without ambiguity as I read it. Had a really nice link a couple of years ago to it, but that was then, not now.
=

Maybe this can give an idea?

"The concept of finding a good configuration of binary variables (switches) in this way lies at the heart of many problems that are encountered in everyday applications. A few are shown in figure below. Even the concept of scientific discovery itself is an optimization problem (you are trying to find the best 'configuration' of terms contributing to a scientific equation which match real world observations)."

http://www.dwavesys.com/tutorials/background-reading-series/quantum-computing-primer

===

And no, remember Feynman Paths zx16?  That's how I think of it any way, as if a quantum computer was supposed to 'take' all of those paths 'simultaneously' (another great example of where something are supposed to do 'several things' simultaneously, but not in a classical way) so arriving to the only way left, as the other takes themselves out. The fuzziness disappear, depending on the quality of the question.
==

what I really wonder about is if there couldn't be a theorem defining it? The relation between ones try for a stringent unambiguous question, relative a answers quality? Maybe also defining limits to it? Maybe there is and I've missed it though.

12

Physiology & Medicine / Re: What happens to your pupils when you close your eyes?

« on: 06/11/2016 17:05:25 »

...What happens to your pupils when you close your eyes? Do they dilate as they would in the dark? ...

Initiating eye-movements tells the brain to ignore the information from the eyes, as during eye-movement the image on the retina would just be a confusing blur ... https://wikipedia.org/wiki/Saccadic_masking

Something like ...
"Eyes are about to move, ignore visual input, (and buffer), until eyes are stationary".


Possibly something similar occurring during eyelid-movement which overrides automatic pupil dilation.

 Something like ...
"Eyelids are about to blink, so it's going to get dark for a moment, but don't increase the aperture".


 

13

Chemistry / Re: Why do we add elements to the periodic table that decay instantly?

« on: 03/11/2016 08:13:12 »

the element "Hydrogen" at the far left.  And "Helium" over at the far right.  Between these two elements there's nothing but a row of empty squares.How do you explain that?

The chemical properties of an element depend primarily on how many bonding electrons are in the outer shell.

Since the periodic table was developed by chemists, it's not surprising that they would want to classify elements according to their chemical properties.
- Helium has 0 bonding electrons, so it logically groups with Neon etc.
- Hydrogen can be considered to have 1 electron in it's outer shell, which sort of groups it with Sodium.
- But Hydrogen can also be considered to have room to hold 1 extra electron in its outer shell, which would group it with chlorine.
- So Hydrogen is a bit of a "floater"

There are some other organizations for the periodic table which try to represent these characteristics without any "gaps"; but some of them take up more than 2 dimensions!

See: https://en.wikipedia.org/wiki/Alternative_periodic_tables
 

14

Physics, Astronomy & Cosmology / Re: If a hole were drilled through Earth and you jumped through, how would you exit?

« on: 03/11/2016 00:56:30 »

Neglecting air resistance (and other impracticalities), you would oscillate back-and-forth between the two sides of the planet with simple harmonic motion. You would accelerate downwards from one surface, reach a velocity maximum in the region of the Earth's centre and then decelerate to a standstill at the opposite surface.

That's theoretically true - if a perfectly symmetrical spherical object, such a ball-bearing of finest precision, were dropped into a hole drilled through the centre of a perfectly symmetrical planet.  The ball-bearing would oscillate endlessly back and forth.

However, the OP posits that "you", ie presumably a human being, jumps into hole drilled through "Earth".
 
Earth and humans aren't perfectly symmetrical.  Humans have more mass in their head than in their feet, and Earth has more land-mass in the Northern Hemisphere than in the Southern.

Wouldn't these asymmetries affect the oscillations, until the OP's human eventually stepped out of the hole, probably at the South Pole end?

The crust is pretty thin compared to the Earth as a whole.  If you average out the oceanic and continental crust thickness, it averages out to ~13.3 km.  It is also less dense (2.2 g/cc) than the Earth as a whole 5.52 g/cc.   In the end it works out that the entire crust amounts to about 1/400 the mass of the entire Earth.   And while the continental crust is quite a bit thicker than the oceanic crust, you also have to remember that it is floating on the mantel, so it extends deeper into the mantel than the oceanic crust does, displacing some of the denser mantel.  If fact, it displaces exactly the same mass of mantel as the mass of the continent crust floating there.   The continental landmass does not add to the total mass in that part of the Earth.   This isn't to say that the mass distribution is totally homogeneous, but the effect of these variations will be extremely small, and likely swamped out by other factors ( the oblateness of the Earth for one.).

15

Cells, Microbes & Viruses / Re: Why does the skin on my fingers wrinkle when I stay in the water too long?

« on: 02/11/2016 22:57:43 »

Its an evolutionary adaptation.  The wrinkling increases your ability to grip objects under wet conditions, thus the body is conditioned to cause those wrinkles under the proper stimulus.  One of the clues that led to this conclusion was that people with nerve damage did not get this wrinkling when their hands were soaked in water.

16

Chemistry / Re: Why do we add elements to the periodic table that decay instantly?

« on: 01/11/2016 01:30:11 »

I don't think that the rare Earth elements (f block) had to be forced into the periodic table... They fit very nicely, that bit usually gets yanked out so that the dimensions of the table are closer to that of a page in a book or a poster. An extended version of the table can be found here:

https://upload.wikimedia.org/wikipedia/commons/thumb/2/22/32_column_PT.jpg/650px-32_column_PT.jpg

17

Chemistry / Re: Why do we add elements to the periodic table that decay instantly?

« on: 31/10/2016 19:39:44 »

Is not the reason for the hunt for elements with ever shorter lives the dream that past 118 there maybe at 126 "an island of stability" with a relatively long life and interesting properties.

Yes, and perhaps this "dream" as you call it, is a true intuitive reaction against the very idea of so-called "Dark Matter".

What if "Dark Matter" isn't some alien thing made of weird particles, but consists of ordinary proton/neutron elements in the "island of stability"  -  at 126, and possibly other "islands" beyond.  Elements like these, would probably have long-lives and "interesting properties", as you say. 

Such properties might account for observations such as anomalous galactic rotations. These are currently ascribed to the presence of "Dark Matter". Couldn't they be due to the presence of "super-heavy" elements which are higher in the Periodic Table than we've yet discovered?

I think this is highly unlikely. Dark matter is invisible to the entire electromagnetic spectrum to the extent that we have probed it (between 10^–12 and 10³ meter wavelengths). Atomic or molecular matter made of such heavy atoms would surely absorb somewhere within this region. This apparent non-interaction with electromagnetic energy is why people have posited particles such as neutrinos as explanations of dark matter.

18

Chemistry / Re: Why do we add elements to the periodic table that decay instantly?

« on: 29/10/2016 22:28:45 »

Might there be elements whose nuclei are made of particles of "Dark Matter"?

That is a bit difficult to say, since we don't know what Dark Matter is!
Or, more accurately, it is definitely made up of a variety of different things, but we haven't positively identified the majority of it.

For example, the observed effects of Dark Matter has contributions from:
- Thinly-spread normal stars: These may have been ejected by galaxies during collisions, and be spread so thinly through space that they don't show up in astronomical telescopes behind the glow of Earth's atmosphere. These are made up of regular nuclei.
- Free-floating planets or the dark cinders of small burnt-out stars: These are made up of regular atoms, made of standard matter.
- Neutron stars: These are like a single huge nucleus, with the mass of the Sun
- Black holes: Our equations don't work at the center of a black hole. But it is safe to say that it can't form a stable nucleus, as it will swallow the rest of the nucleus.
- Relic Neutrinos from the Big Bang: These interact only with the weak nuclear force. They ignore the strong nuclear force that holds the nucleus together, so they can't form a stable part of a nucleus (and even if they did, they would be so light that they would not affect its properties in any measurable way). They can be emitted by normal matter during nuclear decay, and they can (infrequently) be absorbed or scattered by normal matter, making them (slightly) detectable. They even ignore the electromagnetic force that holds the atom together. Unbound, they fly straight through matter at enormous velocities.
- Unknown particles that don't even interact via the weak nuclear force (this is the theory that most particle physicists think is most likely at present): These would be even more ghostly than neutrinos, even less likely to form part of a nucleus with standard matter, and even less likely to be detected. 
- Small deviations from Einstein's gravity on large scales (this theory is not very popular): This theory has no need for Dark Matter particles.

"Dark Matter Periodic Table"

If Dark Matter is primarily made of unknown/hard-to-detect particles (as many cosmologists expect), there is nothing preventing these (unknown) particles from experiencing an (unknown) 5th force which would bind them together in a periodic table of their own, forming the equivalent of a Dark Matter periodic table.

And if these unknown particles have antiparticles, they may annihilate, perhaps releasing energy in the form of gamma rays. Several searches of the gamma-ray spectrum are underway at present, in an attempt to detect such events.

See: https://en.wikipedia.org/wiki/Dark_matter#Composition

19

General Science / Re: How can science be correct if theories are always changing?

« on: 28/10/2016 14:53:49 »

The beauty of science is its intrinsic ability to continuously question ideas and to allow several plausible ideas to exist at the same time. Good scientists are open to challenging and reassessing their previous ideas, and are open to accepting new ideas, should the evidence (demonstrated through sound, repeatable study methodologies) demonstrate those new ideas to be more 'correct' than the previous. And those new ideas, in turn, can be challenged again in light of additional information.

We are never really 'correct' but we should continuously seek evidence to minimise the degree to which we are 'wrong'. Nothing in science is ever 'proven'.

This is different to choosing one idea, declaring it 'correct', and continuing to accept it as 'correct' for the rest of eternity.

However, the general public sees this as: "Scientists keep changing their minds. Scientists are not sure if they are correct. They must not know anything." (Which, in my opinion, is a failure of effective science communication in the general news media. But that's a whole other story...)

20

Chemistry / Re: Why do we add elements to the periodic table that decay instantly?

« on: 27/10/2016 01:35:27 »

If we define elements as atoms with unique numbers of protons, then there are already 118 known elements. If we include all isotopes (unique numbers of protons and neutrons), then there are already several hundred. unique nuclei known. I'm sure there are all kinds of crazy elements formed during catastrophic events involving neutron stars, even if they are only short-lived.