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Physiology & Medicine / Re: is there any evidence for genetic memories?

« on: 25/10/2020 11:43:47 »

I think anyone clever enough to haul rocks from Wales to Wiltshire wouldn't be fooled by notions of spirituality!

But there is of course plenty of evidence of powerful genetic memory in other species. Nobody teaches swallows or butterflies how or where to migrate, but they do exactly what their parents did. 

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Physiology & Medicine / Re: is there any evidence for genetic memories?

« on: 24/10/2020 23:30:08 »

I suspect that standing stones and suchlike in the British Isles will make an impact on a Brit because the environment, climate and agriculture are familiar, so we can imagine ourselves somehow involved in the society that constructed them, but a pyramid in a hot desert is completely alien.

We also have a healthy separation of church and state: kings and queens run the army and appoint the civil courts, but we don't worship them as gods, so the excessive veneration embodied in a pyramid is frankly distasteful.

For what it's worth, my theory of stone circles and wood henges is that their primary purpose was for the regulation of trade. We know that lots of cattle were raised in Orkney, probably more than required to feed the population, so there would be good reason to trade for, say, fruit from further south. But there's no point in making a journey of several days or weeks to trade if your opposite numbers don't turn up at the same time and place.  So everyone builds a market hall with a synchronised calendar: the dawn sun at midsummer. Now we agree to meet at, say, Stonehenge, 60 days after the solstice. Knowing how long it takes to walk there, we can organise our slaughter, curing, packing and travel, with a high degree of confidence that we will meet other producers and merchants.  This explains the huge pile of pig bones near Stonehenge - it's an early Travelodge where salesmen meet and eat.   

Genetic memory? Yes, we are indeed a nation of shopkeepers, and we recognise a marketplace when we see one. 

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Physiology & Medicine / Re: Why do even non-believers pray or appeal to God in times of need?

« on: 18/10/2020 01:05:50 »

Before trying to explain why something is true, it's a good idea to check if it is true.

How often does the cockpit voice recorder tell us that someone's last words were"Our father who..."?

I spent some time working with a forensic phonetician. He assured me that the last word on every CVR he had analysed (several dozen) was always "sh1t". It is a remarkable finding: his skills ranged over at least ten major languages, but whatever the native language of the pilot, years of training kick in at the last moment; "in an emergency, speak English".

The only exceptions I know of, were the 9/11 hijackers who attempted to contact some deity before killing 3000 innocent civilians. However they don't count as they were not in time of need.

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Just Chat! / Re: Political split from topic about Darwinism

« on: 07/10/2020 12:20:28 »

We willfully take a diseased male, and inject him with pep pills, so he has enhanced performance for a few hours.

Your premonition was correct! Dexamethasone has reanimated the scumbag, maybe for long enough for the electoral college to ignore the people's vote once again.

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Chemistry / Re: Can Sulphites be removed from wine other than by adding hydrogen peroxide?

« on: 02/10/2020 15:14:37 »

The whole point of adding metabisulfites to wine is to preserve the flavor and inhibit secondary fermentation. Boiling the wine will leave you with a residue of sticky grape sugars and a tiny trace of potassium sulfite, and some rather raw brandy with a hint of sulfur dioxide in the distillate.

Given the choice, I'd rather drink my Mouton Rothschild as it came in the bottle, along with whatever additives the good burghers of Pauillac have deemed fit to use for the last 170 years.

My own garden produces an adequate grape juice, and I sometimes add a hint of  Na₂S₂O₅  to stop it turning into Chateau Calverd, or after adequate fermentation to prevent the Grand Cru turning into expensive vinegar - Sarson's Malt is a better match with chips.

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COVID-19 / Re: Why are coverings not working against Corona virus?

« on: 26/09/2020 14:34:47 »

Masks (particularly surgical masks) are not 100% efficient. The best close-fitting masks that are tolerable for civilian use, are about 97% efficient at trapping 0.3 micron particles but the COVID virus is smaller. A loose surgical mask will stop you spitting on your victim but won't trap much more than 50% of the incoming aerosol from your infectious best friend, and very few people even bother to wear those properly. The chief benefit of "social" masks is to encourage everyone else to wear them so they don't project their exhalate so far.

Parachutes and seat belts fail occasionally, but not wearing them can be 100% fatal.

The reason the numbers are rising is because that's what viruses do. One carrier in a household is almost certain to infect all the others eventually unless they all wear space suits, so once you have infected more than 5% of the population you will probably accelerate to 50%.

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Physics, Astronomy & Cosmology / Re: Life on Venus Finally Found?

« on: 25/09/2020 22:09:08 »

Millions are thinking that the beggining and the ending is on earth,

Mine certainly began here, and although I'd like it to end on Mars, the prospect is receding. I think the consensus is about right on this topic.

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Just Chat! / Re: Is this how research always works?

« on: 19/09/2020 10:54:18 »

It's generally a bit less random than your example suggests. There are four distinct starting points

1. We have an engineering problem with no textbook solution. What is the nearest thing we know that might solve it? Now  simulate the problem in the lab and tweak the solution: are the numbers good enough to build the bridge, or can we improve them?

2. We have an engineering failure. Can we simulate the conditions and find out why?

3. From what we know about X, I have an idea that something interesting will happen if we do Y.   

4. What is happening at Z?

Astronomy sits somewhere in the 3 - 4 region. For 3, the experiment has probably been done somewhere in the universe so let's look for the results. 4 can begin with an observation of something that wasn't there yesterday, or a previously-unnoticed variation in something we took for granted.

The underlying consistency  is in the recursive "observe, hypothesise, test"  algorithm of the scientific method. Most, but not all, research enters at the "observe" phase.

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Physics, Astronomy & Cosmology / Re: Speed of light from different observers?

« on: 07/09/2020 00:08:40 »

So what is it?

It is a measurement of the speed of a wave travelling in one direction.

The joy of a continuous travelling wave is that you don't have to time a pulse over a distance because the speed at any point defines two independently measurable quantities: how many peaks pass that point in a second, and what angle the beam is deflected by if you place a grating at that point.

I didn't subscribe to your earlier etalon suggestion because that requires multiple reflections, so could be argued to be a two-way measurement. The angle at which a beam is diffracted from a simple transmission grating depends only on the wavelength of the incoming radiation and the periodicity of the grating.  Or you can use a zone plate and just measure the focal distance, which is an inverse function of wavelength.

As we both pointed out earlier, these measurements (particularly of f) are difficult at optical frequencies but very easy with microwaves.

The fun bit is that the measured value of c turns out to be exactly that calculated by Maxwell from independent electrostatic and electromagnetic measurements.

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Plant Sciences, Zoology & Evolution / Re: If everything is made of atoms, what is life?

« on: 05/09/2020 23:28:57 »

Life, like beauty, is an abstract noun which is only defined as a property that we ascribe to certain objects that we call living (or beautiful). We can define a living thing as a dynamic array that tends to homeostasis in response to a stimulus.

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Physics, Astronomy & Cosmology / Re: Speed of light from different observers?

« on: 05/09/2020 14:03:58 »

Ditto for the measuring the frequency and wavelength thing, both measurements yielding incorrect results in an absolutist interpretation of the universe.

I don't recommend interpreting anything. For a travelling wave, v = fλ by definition of the terms. Nothing to to with relativity as my experiment works when A and B are not moving relative to one another. The theoretical and demonstrable constancy of c is in fact the basis, not the consequence, of relativity.

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Physics, Astronomy & Cosmology / Re: Speed of light from different observers?

« on: 04/09/2020 09:14:31 »

What device do you think can measure the wavelength accurately with high precision?

A diffraction grating is generally best.

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The Environment / Re: Is it against human rights to make "excessive wealth" a crime?

« on: 03/09/2020 18:05:41 »

The wealthiest people include the Queen, whose farms are at least as carbon-efficient as anyone else's, and who normally travels in a fairly ordinary car - the big Rollers are only brought out for state occasions and probably cover less than 1000 miles per year. The Queen's Flight actually spends most of its life as a military tanker.

We could look at Geoff Bezos or Bill Gates, whose phenomenal wealth has been acquired by making everyone else's life more carbon-efficient.     

Everyone who burns fuel, pays the same tax on it (though it varies from country to country). So taxation is directly related to personal emissions.

Any employer who produces more emissions than his competitors, is wasting money and burning profit. The object of business is to maximise profit - the only way to accumulate wealth. So there is already a strong incentive to minimise the emissions and general waste associated with each product.

But the quantity of product sold, and therefore the total waste generated thereby, is controlled by the consumer, not the producer. So to minimise emission you should persuade the end user to buy less.

If I could halve the cost of food for everyone and still make a profit, I could accumulate wealth beyond anyone's wildest dreams. Why would this be a crime?

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Just Chat! / Re: Where is Administration thenakedscientists.com ??

« on: 01/09/2020 13:09:47 »

It's all in the mind.

 

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Physics, Astronomy & Cosmology / Re: Which forces are directable

« on: 20/08/2020 14:13:55 »

Electric and magnetic fields propagate through space but are difficult to direct over distances greater than the diameter of the source.

Magnetic fields need a return path that doesn't upset other people's computers, but do have the ability to suck some objects.

Gravity sucks radially and not very well.

Electromagnetic radiation of lower frequency than x-rays can be focussed or, particularly in the case of laser radiation, propagated as a parallel beam.   

You can transmit a lot of momentum in a bullet.

Wherever I have to move an object at a distance, my first preference is to use a stick or a string.

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Technology / Re: Is there a relationship between a transformers core area and its VA rating?

« on: 17/08/2020 09:20:51 »

Ac = (Vrms x √2) / (2 x Pi x f x N x B)

Interesting to see that the formula says √2 / 2 instead of just 1/√2. The reason is that for a sinusoidal waveform Vmax = Vrms x √2, so the concern is with core saturation at peak load and it is true for all waveforms if you substitute Vpeak.

However as Evan says, the real effect is due to Ipeak so the formula is only a good approximation for low f, unity power factor and no secondary load.

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Technology / Re: Valve connected to the cloud make sense?

« on: 07/08/2020 14:00:06 »

Noninvasive flowmeters using Doppler ultrasound are cheap and effective but far too analog, simple and reliable to be of any interest to a software developer! 

If you are inserting a valve into the flow,  you might also consider adding a vortex-shedding flowmeter.

One presumes that a mechanical valve knows whether it is open or closed by the position of its actuator, but the absence of flow through an open valve, or residual flow through a closed one, might be a useful diagnostic. 

A crude flow detector does have an important mass application. In the civilised world and the United States, people use piped water at home. The simplest nonintrusive monitor  of an old or disabled person's state of health  is how often they open a tap or flush the toilet. No flow during daylight hours, or continuous flow for 24 hours, suggests that they need help, so a cheap microphone could usefully raise an alarm, whatever the source of the noise in the pipe.

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Physiology & Medicine / Re: Why Do We Sometimes Miss A Word Out When Writing A Message?

« on: 03/08/2020 15:09:34 »

Your mouth and brain move quicker than your fingers. Mouth keeps pace with brain, brain assumes fingers are in step.

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Physiology & Medicine / Re: Are All Instances Stored As A Memory, However Banal.

« on: 02/08/2020 23:07:08 »

Chances are that we synthesise plausible memories in response to some triggers, and polish the synthesis with other memories. This seems to happen under friendly interrogation of a witness: "What happened next? Can you remember what happened before...." and an entire scene gradually emerges that is at least plausible and possibly accurate, though as has often been demonstrated, quite significant chunks may be missing - the classic "gorilla experiment" is a fine example where the implausible doesn't even register in the short-term memory.

The video game is a potential clue too. What you see in a video game has no implications for real food, real sex or real fighting, so it does not make plausible connections with the deepseated things that matter. I've looked at methods of teaching people to take x-rays. If they study the science, pass the theory test, then x-ray real patients, they generally forget the theory within a year, but where we have first taught the practical side and coached a student through a real patient episode, the later theory tends to stick. Or, as the medics say, "See one, do one, teach one."

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Physics, Astronomy & Cosmology / Re: How Do We Know Absolute Zero Is The Temperature It Is If It's Unattainable ?

« on: 02/08/2020 13:48:34 »

Absolute zero is the lowest temperature possible........
How do we know this if Absolute Zero Is unattainable ?

Make up your mind!

Anyway, the concept is derived from the Carnot efficiency equation for a perfect heat engine, η = 1 - T_cold/T_hot.
For any nonzero value of T_cold, η < 1, and we can measure the efficiency of real heat engines and show that they follow this law.

So we can hypothesise a zero value of temperature and an absolute scale such that any heat engine with a cold source at T =0  would have η = 1

The problem is one of "thermal relativity". If we have a hypothetical heat sink at T = 0 and a heat source at 0 + δT,  the efficiency with which we can extract energy from it decreases toward zero as δT → 0  so we need to expend an infinite amount of energy to cool it to T = 0.

The idea that there is no motion at T = 0 contradicts Heisenberg, as we would then be able to predict the momentum (zero) and position (right here) of a particle, with zero indeterminacy.