Are more crimes committed during a full moon?

Chris Smith put Muhammed’s kid's question to Imperial College's Stuart Higgins...

Stuart - It’s an amazing question. and you’d think actually that soaps contain all these different dyes in them that absorb light of different colours so why isn’t that colour reflected in the foam? Things look like a certain colour because when the light hits the object it’s either absorbed or certain wavelengths are reflected, but, actually, in this case we’re getting lots of different wavelengths reflected. So, even though there is dye in the soap it has this certain colour, so much light is being scattered back to us and reflected back to us that actually we perceive it as white.

There’s a great experiment and I don’t know if any of you have done this with Marmite?

Chris - Do you love it or hate it?

Stuart - Oh I can’t stand Marmite itself but this is a great. You can do this at home. If you get a bowl and put some marmite in it and you get a whisk and you start whisking the Marmite. Marmite is this really sticky dark brown substance and you think well lights not being reflected from that. But as you whisk more and more air into it you create a foam of Marmite and then actually it starts to go paler and paler. And then, eventually, it starts to turn this sort of white cream colour.

Chris - And you discovered this how?

Stuart:: Practice…

Chris - It really goes white?

Stuart - Yes, if you whisk it far enough. It’s kind of like a beigey white. But yes, if you really put enough air into it, it will eventually go foamy and it will start to look white.

Chris - Can you make Marmite meringues then?

Stuart - Oh that horrible! Ughh!

Chris - That’s a horrible thought…

Stuart - Yeah.

Chris - But from a physics point of view, would it happen?

Stuart - I guess if you could somehow get the Marmite to spread out and be dispersed, as we say, into a mixture of egg and protein then maybe you could. That sounds like a great idea. I might try that later.

Chris - And just to return to the soap point of view, away from the Marmite. It’s the same principle then that when you look at snow, this is white despite the fact that you’ve got water, which is transparent, that makes it, you end up with white snow because it’s lots of little crystals of ice which are doing pretty much the same thing. Milk probably the same, or Dettol, when you pour Dettol or detergent in water you get it going into a cloudy white colour and that’s little blobs which are bending light in the same way.

Stuart - Yeah. It’s all to do with...does this material we’re looking at have lots of different angles and complex structure that can cause light to scatter and reflect in lots of different angles?

Chris Smith put Tony's question to Cambridge University's Maud Borensztein...

Maud - The body is made up of very different types of cells. If you think about a red blood cell, for example, that is a very tiny cell compared to nerve cells. Nerve cells can reach lengths over a metre so it’s a bit difficult to do an approximation of the weight of a single cell.

Chris - Shall we have a straw poll? James - how much do you think a cell weighs?

James - It depends which cell you’re talking about Chris, I suppose.

Chris - What cell would you like to estimate?

James - Red blood cell.

Chris - Okay, how much does a red blood cell weight?

James - I would say about… a thousandth of a gram.

Chris - One milligram. James is going for a milligram. What do you think Stuart - does that sound within the realms of of possibility?

Stuart - Well, you said 3.7 trillion earlier so I’ll try and divide that by…

Maud - Yeah. In between 3.7 and 30 trillion.

Stuart - I’m going to go for a bit less than a gram. Round it to one - physicist approach.

Chris - Maud, put us out of misery then.

Maud - We can more or less do an approximation of under one nanogram.

Chris - A nanogram?

Maud - Yes, a nanogram. So we can imagine…

Chris:: So, James is a millionfold out then?

Maud:: Yeah, exactly. We can imagine to do a gram of cells we would need nearly a billion.

Chris:: Wow! That quite light isn’t it?

Maud - Yeah.

Chris - But you did say, and James was crafty he said which sort of cell are talking about because some cells, like you say, are muscle cells - a big muscle cell. Some of them are a foot long aren’t they?

Maud - A muscle cell will be a lot easier. Even like an adipose cell, fat cells for example. There’s a question of size but also a question of weight. A fat cell will be lighter than muscle cells even if both are quite big.

James - Because I imagine, as you say Chris, the muscles of your quadriceps or your hamstrings - a foot long - got to be up there 10 or 20 grams, probably more isn’t it?

Chris - I would think probably because that’s one of the biggest muscles you’ve got apart from you gluteal muscles in your bum. They are, I think, the ‘king’ muscle, aren’t they?

Chris Smith put Josip's question to Imperial College's Stuart Higgins...

Stuart - Do you know what Chris, I have to be completely honest here, I had no idea about this question. Even as a physicist, even having a physics degree, I had to go and consult a more specialist physicist - I had to go and find a cosmologist and ask him. So thank you to Dr Roberto Trotta, Imperial College’s theoretical cosmologist So I went and had a very nice coffee with him and he kind of blew my mind.

There are lots of different ideas here but, what I should say is, these are theories, these are ideas and consequences of the mathematics that cosmologists have come up with. Not all cosmologists agree about these. But in the same way that we know about the big bang model and our understanding of the universe, if you start to look at more complicated maths, start to consider what are the consequences of different models that created the universe, then there are some interesting outcomes. It could be, actually, that our universe isn't the only one, that other universes have budded off at a certain time and have very different properties to our own. That they could have different numbers of dimensions, that they could have different constants to the laws of physics where the speed of light is somehow different, or something else entirely.

And on top of that it gets even more complicated when you consider things like the quantum multiverse. One way of interpreting the kind of mysteriousness of quantum mechanics is that when you make a decision, the universe splits out into all the different variants of different ways that decision could have gone. And so you end up with this very complicated system of theories where you have different universes, each of which might have millions of quantum multiverses on top of them, so it’s very complicated.

And the answer is: these are all theories and we can’t yet measure anything to give us an indication of what they are. They’re consequences of maths.

Chris - Michio Kaku came over from New York and gave a talk here in Cambridge about ten years ago to coincide with the release of his book “Parallel Universes.” And he said: well, one of the ideas of the big bang that occurred in our universe, its origin, you can think of it like the big bang is a white hole which occurs at the arsehole of a black hole in another universe. So sort of one universe is spawning other universes out of it’s black holes. Did Roberto Trotta comment on that at all?

Stuart - He didn’t specifically use that language no.

Chris:: Neither did Michio Kaku, but I’m sort of adding colour.

Stuart - Okay, okay. But it’s very interesting and it is one of those things. So I’m experimentalist and I always want to the see the data, I always want to see what the measurements are but, actually, at the same time you need to be able to theorise these things so you know, as experimentalists, what to look for. And maybe, in the future, when our instruments get better as we’re able to detect more exotic things like gravitational waves, we might start to see signatures of what’s beyond our current understanding of the universe.

Chris Smith put Luke's question to Cambridge University cardiologist, James Rudd...

James - It’s a good question Luke and the answer is yes. In fact, since about the 1970s superglue, in a much more dilute form than you’d buy in your local hardware store, has been used for just this purpose. The super glue we use in hospitals is of what we call a medical grade, so it’s checked for sterility to make sure it’s sterile and make sure there’s no bacterial viruses in there. But it works very well and head to head studies with traditional stitches have shown that the glue, in many cases, is superior because the act of actually putting a needle through the skin to introduce the suture actually is another portal for infections to get into the wound and cause wound infections. So for certain kind of incisions superglue, or it’s more dilute cousin shall we say, is very good. The glue is generally applied to incisions that are quite shallow, particularly on the face because you don’t then get the associated small holes where the sutures have been placed. And rather than being worried about super glue sticking there forever and it being hard to get rid of, we know that the superglue after three or four days actually comes away quite easily once the wound has begun to heal underneath it.

Chris - Does it work it work it’s way out through the surface then - is that what happens, the glue is shed with dead skin?

James - Exactly. As the epithelial cells die and are replaced, the layer with the glue slowly sluffs off.

Chris - So you haven’t got a layer of Loctite left in your face for the rest of your life?

James - No, exactly.

Chris - Thank you James.

Chris Smith put Neil's question to Maud Borensztein from Cambridge University...

Chris - Now I like that idea very much but is that a myth or could it happen?

Maude - I do also like this idea but I would prefer chocolate if I would have the choice. But you won’t 'strawberry-ify' your milk but what we know now that a change in what you give to your cow could slightly influence the taste of the milk. So there are two studies that have already been published and it seems that when they add strong flavour to the food there’s a slight tell that have been found in the milk. And this is something that is found also, for example, in France with the cheese. For the gruyere or the beaufort we have two kind of cheese, we have the summer one and the winter one, and it seems to be because of what the cow will eat. During the summer they will eat grass and flowers, when during the winter they will mostly eat hay and it will slightly change the taste of the cheese.

Chris - Stuart…

Stuart - I heard something as well that if you fed certain animals say poison ivy or something that they could develop in their milk some kind of antidote or some kind of resistance that would be produced by the milk afterwards that you could use the animal almost to kind of create a...

Maude - I know that what is important with the milk that you can give to the baby.

Chris - Oh yes, you’re talking about antibodies, in like colostrum and things because that can change the microbes that live in your gut. I wondered when you were talking about breastfeeding whether you were going to explore this whole idea about what the mum eats affects what the baby grows up wanting to eat or has a particular predilection to want. You’re nodding James - is this something you’ve seen?

James - I’ve certainly heard it said that what the mother eats can make breast milk more or less palatable to the baby. Now as to whether it affects the babies or child’s food choices later in life. Is this the Mandela effect Chris?

Chris - Aha. I have seen studies that have looked at what goes into the mother’s mouth and then what ends up in her blood, and there are certain proteins which you can then trace. People have done tracing studies and they can show them coming through in the breast milk and so there is a suggestion that certain food stuffs do influence the composition of breast milk and that can include strongly flavoured chemicals, particularly garlics and onions, allium family type things and that may have an impact on what the baby likes. Kyle?

Kyle - I’m certainly no expert on this but I have two small children who I did breast feed. So I read a lot of literature and certainly it’s given that you will have these differences that come through in the milk from what you eat. But I think there’s a lot of real new research about the gut and, again, I study the brain so it’s a bit outside of my field, but there’s some fascinating stuff that I’ve read about the effects on the gut biology and the fact that we are just learning more about the biota that’s there. So we know that cesarean sections, for example, is changing the gut biology of the babies born by cesarean. So I would be curious if the breast milk, the breastfeeding is changing that too. I don’t know of any research on that.

Chris - Kyle; thank you very much.

Chris Smith put Sereen's question to Imperial College's Stuart Higgins...

Stuart - No, and that’s because the energy that comes out of those sparks is far too small to ignite the material that your bed is made of. But, actually, there are circumstances where it could be a problem and the classic example is at a petrol station.

Chris - How many people sleep in a petrol station, Stuart?

Stuart - That’s true, that is very true. So if you’re in bed you're okay, but the way you have to worry about this is something like… Well, actually, do you know why you have to hold the handle in the UK? So, if you go the U.S or Germany you don’t have to hold the handle while you’re filling the car.

Chris - At the petrol pump?

Stuart - At the petrol pump yes.

Chris:: Because it’s earthed!

Stuart - Yes, exactly. They’ve found that if you have a system where you go and put the petrol pump in, you squeeze the handle and you lock it in place so you can walk away. People tend to go and sit back in their cars and as they get out of their car again their clothes are rubbing against the seat and it’s generating this static electricity. And the first thing you then touch is the petrol pump, with the vapour, and then in that case the energy from the spark, which is about 8 kilovolts, is enough to ignite the petrol fumes. Very low risk, doesn’t happen a lot, very, very few reported cases but it’s one of the reasons why, in the U.K., you have to squeeze the handle while you’re doing it.

Chris - Is it fashion dependent? People who have a persuasion towards a particular latex or nylon underwear or something? Are they more prone to having a fuel tank fire?

Stuart - Potentially. The ability to charge clothes by rubbing them against different surfaces depends on what that material is and certain materials, yes, are easier to charge up than others.

Chris - You can sleep easy on that piece of advice. Your bed sheets are not going to cause an inferno while you’re sleeping.

Chris Smith put J.J. Vigganio's question to Kyle Treiber from the University of Cambridge....

Kyle - There are thousands of factors that we know are associated with crime involvement and some of those are individual, some of those are biological, others are psychological but we also have mainly social aspects, environmental factors that we know predict crime. And I think once we are understanding more and more not only how many factors, but how interactive those factors are, we talk about multi-factorial effects, so, for example, it’s not going to be one gene. We have found very little evidence of any single gene having a huge influence on criminal behaviour. In fact, there seem to be many, many genes involved in any kind of outcome, physical or behavioural and, of course, behaviour is a whole other dimensions. Similarly, there are also very many environmental effects that are interacting with those genetic effects. So, ultimately, what we have are very small influences across many factors. So I think, actually, rather than saying is there any room left for free will, I think it’s quite clear that there’s plenty of room for free will because not any of those factors is going to be so influential that we have no options or choices but to do what it’s influencing us to do.

Chris - There’s a study from the U.S. last year which I remember reporting on. I was quite stuck by it, but they were showing it’s correlation not causation. You’ve got to be very careful how one interprets this but there was a lady showing that where you grow up, in terms of your exposure to pollution, strongly influences your likelihood of getting in trouble and having behavioural problems or even being dyslexic. And so, they were showing this strong correlation between maternal exposure to pollution and then these different behaviours in the children. So I guess that would be a good example here, wouldn’t it, in that the environment in which you grow up? The same individuals they controlled the study quite carefully, they compared individuals who lived in polluted and non-polluted parts of cities, there was this really quite profound effect.

Kyle - We see a lot of research that is like this, and it’s very interesting because it does suggest that something is happening. But a lot of what may be happening may not be a causal effect in the sense that the pollution is causing that, so the pollution may be having some effects on development which we could study and look at. But, arguably, there’s also going to be selection effects about the kinds of people that live in these neighborhoods. And those individuals, that selection of those kinds of individuals into this environments may be having more of an influence on the outcomes of the children than actually the pollution itself.

Chris - And the questioner mentions the fact that it very often is men. Why are we more prone as men to do naughty things compared to women, or are we?

Kyle - Well, one thing to think about is that it’s not being male that makes you more prone. So there are very many men who do not commit crime, far more than actually do and have any kind of criminal conviction. Being a male does not make it more likely that you will offend. There are certain things about males that may mean that you are more likely to be in situations that you would be vulnerable to offending.

Chris - More likely to get caught? Kyle - You could be more likely to be caught. There could very much be a selection effect that the police are more likely to arrest you or you’re more likely to get convicted for your crime. Chris - Women are better planners?

Kyle - Well, I mean we could argue that all day but as far as crime involvement goes I think there are a lot of differences. What we look at, for example, differences in what women think are right and wrong behaviors to do, their levels of self control. But also, in particular, their exposure to different kinds of environments, how much time the spend unsupervised with peers, handing out at night, drinking alcohol in city parks and so forth.

Chris - Interesting. James…

James - I was just going to come back to your point Chris about pollution and how it can really affect not only potentially your risk of future crime, but also there’s a very strong link with heart disease as well. And, in fact, it’s an inverse square law: the further you move away from the road the less your chance of heart disease.

Chris - And do we know why? James - It’s thought to be the nanoparticulate, the very small bits of pollution that can get straight into the bloodstream through the lungs and they can increase stress on the heart. Chris - How? James - Atherosclerosis, so hardening of the arteries; it exists in most people. But people with high levels of these pollutants in their blood, there’s more inflammation and this can lead to plaque rupture and heart attack.

Chris Smith put Donald's question to Imperial College's Stuart Higgins...

Stuart - So stars and planets are formed in these giant dust clouds and, initially, it’s gravity that starts to bring things together. And the star forms and the gas cloud collapses on itself and the gravity pulls in and, eventually, at some point, nuclear fusion starts the process the force is so great, and a star is born. With planets when you’ve got dust circulating the existing the systems.

Now, initially, as different atoms pass, they might bind together and form molecules and these might start to aggregate and get into slightly larger dust particles. But, actually, there is a problem here because when dust particles start to get bigger and bigger, when they bash into each other they don’t necessarily stick, they bounce off each other like two pool balls hitting each other, and this is an ongoing puzzle in science. It’s not clear what the answer is.

Some people think that it depends on the shape of the dust particles. So, if the dust forms in a very irregular way - they call it a fractal way, it’s a very rough surface and the chance of it sticking when two pieces come together is quite high. Some people think maybe that there’s some organic material in there that’s more sticky that might add to that mix, or maybe ice or frost, but it’s a really big puzzling problem. It’s called the metre-sized problem, which is how do you get from bits of things that are in an order of centimetres up past a metre without them bashing off each other so that they split apart again or that the become too big that they suddenly fall into the star they’re all orbiting?

Chris - Is it not just the fact that when you’ve got millions/billions of particles all in one place that you’ve got billions of goes at the more kind of bashing into each other with different amounts of momentum, coming from different directions and, just by chance, a few are going to cancel each other’s movement out exactly and hang around together And then, once you’ve got fewer of those, a few more of those join in and eventually, with enough rolls of the dice, you get there?

Stuart - Yes. So potentially, part of the problem is that when people study this they literally get dust and fire it at each other and record it with a high speed camera. And that give you some indication; it shows you how things bounce off each other, but it doesn’t necessarily reflect the environment the particles are moving in. So, for example, some people, or some scientists believe that if your large particle is moving through a gas flow and a bit flies off, that small bit that flies off is going to fly straight into a gas stream, be pushed back towards the big particle again. So it all depends and basically it’s complicated and we're still not sure exactly what happens.

Chris Smith put this to University of Cambridge's James Rudd...

James - So again, it’s a really good question and very topical at the moment. There are three or four different types of dietary fat and Elizabeth is referring to what we call polyunsaturated fats - omega-3 and omega-6 being the main ones that we consume. Long-term studies of something called the Mediterranean diet, which takes advantage of the fact that people in southern France, southern Italy, and Spain have less heart disease than people in the north of Europe. They seem to consume a lot more oily fish, and oily fish such as salmon, fresh tuna, mackerel, herring, etc. are very rich in omega-3 and this has been shown to be a significant factor in reducing the incidence of heart disease.

Now, the second question, which I am often asked in my outpatient clinic, is can I take supplements. I don’t like oily fish, can I take pills - omega-3 pills - instead of eating oily fish? The answer is: it’s fairly clear that supplements are not as good as eating the fish itself. For vegetarians out there, there are other options that contain omega-3, such as flax is one that is well recommended and that seems to have some beneficial effect.

Chris - Do you believe this or do you think it’s just people who don’t eat fish in their diet probably don’t eat other things that are also positive in terms of their impact on your health and so we’re attributing that to a lack of fish or omega-3 fatty acids and its other  health effects?

James - The studies have actually been fairly rigorous and they have controlled for other areas of the diet that might be deficient. And the recommendation from societies like the British Heart Foundation, which is leading in this area, is that we should eat oily fish twice a week and one of the portions should be around 140 grams, and that does have a very positive, beneficial effect on reducing the chance of heart disease.

Chris - Good for brain development as well, I’ve heard. Is that true?

James - I believe so, yes. At a much earlier age, obviously than we’re talking about preventing heart attacks but, yes, I think there is an effect there as well.