Ep 160: 2015 The year of light

2015 was a magnificent year for physics. Not only was it the International Year of Light and light-based technologies, it was an outstanding year of astronomical achievement, culminating with the magnificent New Horizons photos of Pluto. It was also 100 years since the Theory of General Relativity was published, and 50 years since the Cosmic Background Radiation was discovered.

Australia also broke a couple of astronomical world records: The most people stargazing across Australia, and in a single location at ANU. One of the organisers of this world record was Tom Gordon, a science communicator at The University of Sydney who runs Kickstart Physics (Instagram), which are physics workshops aimed at year 12 science students and teachers. Tom, along with Christie McMonigal and Shane Hengst, runs the STEMPunk podcast, chatting about science communication and Science, Technology, Engineering and Mathematics (STEM): Communicating scientifically with science communicators.

Who better to talk to about this splendid year in Physics than Tom?

Listen in here:


Songs in this episode (in order of play - all Creative Commons Attribution Noncommercial (3.0)):

1. Sharks with Lasers by spinmeister;
2. Red Giant by Fireproof_Babies;
3. Fate of the Sun by Fireproof_Babies;
4. Beyond Jupiter - Instrumental by Ivan Chew;
5. Spaced Invaders 2011 (90 BPM) by coruscate
    
   

Who you gonna call?

Dial 000 - Police, Ambulance, Fire Brigade...... Or Science!

Ep 159: Wedding cost, marriage success and cats

From a recent chat with ABC Central West, this week is definitely a correlation of the week. Two separate stories on the topic of love and attachment highlight a couple of statistical concerns you need to be wary of when drawing conclusions from research:

1. The correlation of wedding / engagement ring cost and marriage longevity (concern: correlation does not necessarily equal causation);
2. Does your cat really love you? (concern: sample size)

Listen in below or on the mp3 (and all credit again to ABC and Kia).




References:

• Francis-Tan, A., & Mialon, H. (2015). A DIAMOND IS FOREVER” AND OTHER FAIRY TALES: THE RELATIONSHIP BETWEEN WEDDING EXPENSES AND MARRIAGE DURATION Economic Inquiry, 53 (4), 1919-1930 DOI: 10.1111/ecin.12206  
• Potter A, & Mills DS (2015). Domestic Cats (Felis silvestris catus) Do Not Show Signs of Secure Attachment to Their Owners. PloS one, 10 (9) PMID: 26332470

Science Week 2015

National Science Week has come and gone for another year. This year, I spent a lot of it down at Canterbury Public School where I am their tamed scientist as part of CSIRO's Scientists in Schools program. It was a lot of fun, and we walked away with a world record - more on that in a bit. Here's some of the cool stuff we did:



Above is my box of household products for various experiments, and the results of cabbage indicator. Cabbage indicator is made by simply boiling purple cabbage. The resultant solution contains a chemical called anthocyanin which exists in an equilibrium of three forms depending on the ph, allowing a wide range of colours. We used mould remover (strong base), window cleaner (mild base), lemon juice, vinegar and tartaric acid (mild acids).



We've made corn flour slime before, but if you make it with tonic water, it will fluoresce under UV light and glow in the dark. Tonic water contains quinine, which apart from fluorescing, is also a preventative for malaria (which is why it was put in tonic water in the first place). And here's some phosphorescence:



None of the kids had seen an overhead projector before. This demonstrated some basic optics regarding mirrors and light travelling in a straight line, as well as how old I now am. The food colouring / milk / detergent experiment works in the same way our detergent-powered boat works, noting that the fat in the milk helps keep the food colouring separate (it doesn't readily dissolve until the soap is added).



Liquid nitrogen is always good (as was the liquid N2 ice cream we made), as is entertaining your local MP and making a homemade periscope.



And on that world record, we participated in the world record stargazing attempt for most number of people gazing at the stars at once across many sites. And we got there (unofficially at the time of writing anyway). It was dark, I didn't get many shots, but I did get this one of our planetarium and star demonstrator...

Ep 158: Food science with ABC Radio

Every month, I chat with ABC Central West and the science topics of the day, and this week we chatted food, in particular:

1. Consumption of spicy foods may lead to a lower risk of death (and a little about correlation and causation - I really should do some more correlations of the week)
2. Human brain evolution needed carbs
3. 3D printed food

 Have a listen below, or on the mp3 - all credit to the ABC (and the wonderful host, Kia).

Ep 157: Where to now for Cold Fusion?

Do you remember Cold Fusion? Remember when electrochemists Martin Fleischmann and Stanley Pons claimed to have achieved nuclear fusion in a bottle on a table in their lab in Utah? That was so 80s! Cold Fusion was quickly debunked and, apart from its appearance in a 1997 Val Kilmer Movie (The Saint), most people forgot about it. So it may surprise you to hear that Cold Fusion research continues to this day, with some “interesting” participants and some extraordinary and surprisingly persistent claims. The most recent International Conference on Cold Fusion (ICCF-19) was the largest yet reflecting a climate of renewed interest.

Dr. Timothy J. Surendonk has a passion for cold fusion, and in this podcast episode, tells its story, of the new players, recent events, and particularly the curious story of the “e-cat.” It isn't heavy on technical science, but rather a more entertaining talk that just might challenge the way you relate to science.

Listen to this show here:



References:

• Fleischmann, M., & Pons, S. (1989). Electrochemically induced nuclear fusion of deuterium Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 261 (2), 301-308 DOI: 10.1016/0022-0728(89)80006-3
• Kim, Y. (2009). Theory of Bose–Einstein condensation mechanism for deuteron-induced nuclear reactions in micro/nano-scale metal grains and particles Naturwissenschaften, 96 (7), 803-811 DOI: 10.1007/s00114-009-0537-6 
• Kim, Y. (2012). Nuclear Reactions in Micro/Nano-Scale Metal Particles Few-Body Systems, 54 (1-4), 25-30 DOI: 10.1007/s00601-012-0374-6

Songs in the podcast: 80's synthesizers in space by greg_baumont   Proton Pumps by davi roque de souza Nuclear Winter - Neon Pimpz by DJStupid	Banner:  Big Bang / Cold Fusion by Johannes

Farewell Darren

It is with great sadness that I let you know that my friend and co-Beer Drinking Scientist, Darren Osborne, passed away in January after a brave battle with brain cancer.

I've put a few words up over on the BDS website, so I'll direct you over there if you would like to have a look or if you would like to make a charitable donation to the Cure Brain Cancer Foundation.

The clips in this show might not be new to Mr Science Show listeners, but they are new to those who listened to BDS and are a nice collection of irreverent and ridiculous scientific conversations between us.

Science for kids - Slime

Everyone likes slime! And it's easy to make, in its various forms.

Cornflour Slime:
All you need is cornflour (made from actual corn - maize - not the "wheaten" version you can get in Australia, which is made from wheat), water, some colouring, a bowl and a spoon. The process is:

1. Pour cornflour into a bowl,
2. Stir in small amounts of water until the cornflour becomes a thick paste. I prefer to have the water coloured at this point, as it helps to more effectively spread the colour throughout the slime.

And that's it. Try stirring the slime slowly (should be easy) and then quickly (should be almost impossible). Then try punching it. I employed a professional hand model for this video.

Cornflour slime is a shear thickening non-Newtownian fluid - the viscosity of the slime increases as the shear rate (how quickly you stir, how hard you punch) increases. This is because the slime is a suspension of corn starch. The corn starch molecules are large and jagged and when stirred slowly, the molecules have time to move past each other, lubricated by the water. When a large force is applied, the molecules are jammed quickly together and the liquid does not flow - it becomes solid-like. You can keep it for about a week in the fridge before it starts to smell a bit like vomit. You may need to add a bit of water each time you use it, and stir it in slowly (you won't have much choice).

Packing Peanut Slime (Borax Slime)
A less cool, but nonetheless fun to make, slime is made from packing peanuts - the stuff used to protect fragile objects when you mail them, move house etc. Packing peanuts are generally made from starch but also contain PVA - polyvinyl alcohol. Place about 5 mL of water in a cup and add about 8 packing peanuts and stir. They will start to dissolve. Continue to add the peanuts until it starts to become thick, and then some food colouring.

At this point, you need to have gloves on (and eye-wear if you have some). Add 1 mL of 4% sodium tetraborate solution (borax) and stir. You may have some in your laundry as it is used for cleaning clothes. Your goo will now start to become slimey. Once you can make a solid ball out of it, start to wash it with water to wash away any extra borax. After doing this, you can handle it with bare hands.


Polyvinyl alcohol is a polymer - a long molecule with repeated subunits (monomers). The borax cross-links the polymer chains; that is, it bonds one polymer chain to the next. As you add more borax, more crosslinking occurs making the slime thicker.

There is a similar slime you can make with PVA glue, although in this case the PVA stands for polyvinyl acetate as opposed to polyvinyl alcohol. The process is the same - the borax provides the cross-linking between the PVA polymers, except in this case the monomer contains an acetate (CH₃COO) rather than an alcohol (OH). More on this slime here.

Science for kids - Elephant Toothpaste

Gooey stuff is always pretty exciting for kids. This is called elephant toothpaste because, well, that's what it looks like. The experiment is fairly simple. The ingredients are:

• 125ml 6% Hydrogen Peroxide (ask at the chemist)
• 1 Sachet Dry Yeast (powder) + a few tablespoons of warm water
• Detergent
• Food colouring
• Empty bottle
• Funnel

You might want to wear gloves and goggles when handling the hydrogen peroxide. Add the hydrogen peroxide, a few drops of food colouring and a good squirt of detergent to the empty bottle, then swirl the mixture. Separately, combine the yeast with a few tablespoons of warm water and stir until mixed. Put the funnel in the top of the bottle, add the yeast mixture and watch the foam. The bottle will get a little hot (the reaction is exothermic).



The reaction occurring is hydrogen peroxide decomposing into water and oxygen:
2H₂O₂ → 2H₂O + O₂

The bubbles are caused by the detergent capturing the oxygen. The foam is water and the colouring is made by the food colouring. The yeast is acting as a catalyst. The first few times I tried this, I was using yeast well past its used by date, and it didn't work very well, so make sure your yeast is relatively fresh. Yeast contains an enzyme called catalase. Catalase is found in nearly all organisms exposed to oxygen, and helps prevent cell damage caused by the by-products of oxygen metabolism. It actually catalyses this hydrogen peroxide reaction in living organisms.

I did this outside on our grass, and as the by-product is water, it is safe to have on the lawn. If you are inside, make sure you have a tray to capture the toothpaste as it squeezes out. Wearing gloves minimises the chances of your skin coming in contact with hydrogen peroxide. 

If you want to make the reaction more vigorous - in which case you have to wear proper safety gear - then you can use potassium iodide as the catalyst. But you might not have that lying around the house. There is some more info here.

Science for kids - detergent powered boats

This is an easy one, assuming you occasionally clean your dishes. You just need some bread ties, water and detergent. The video is a little unimpressive, but you could dress the bread ties up to make them look like boats.



Essentially, the detergent is breaking the surface tension of the water, and if you break the surface tension behind the bread tie, the tension in front of the tie pulls it forward. Detergents are surfactants, which means they have a polar end (which is attracted to water) and a non-polar end (which is attracted to oil and grease). This is how detergents (and soaps) bond to both oil and water and hence wash your dishes. Water, without detergent, has a strong surface tension, which is created by the water molecules bonding to each other through Hydrogen bonds. The polar end of the detergent breaks the water surface tension by interfering with the hydrogen bonds at the surface - interestingly, the non-polar ends of the detergent, being hydrophobic, stick up into the air.

Science for kids - Water Rocket

Water rockets are one of the classic science demonstrations for kids - exciting, a bit of danger and some interesting science. Make sure you have plenty of space - making this video, I managed to get the rocket to hit the road, a swing set (with no one in it, thankfully) and some trees. We moved to the middle of a cricket field as the rockets can really go a long way. You can buy water rocket kits at toy or sciencey-styled stores. You need to provide a drink bottle, a bike pump and some water.



The science is quite simple. Using the bike pump, you pump air into the bottle (which already contains some water), increasing the pressure of the air (storing potential energy) until the seal on the rocket bursts. The high pressure air forces water out the bottom of the rocket, which propels the rocket forward. This is an example of Newtown's third law of motion (commonly known by the expression: for every action, there is an equal and opposite reaction).  

Science for kids - Coloured flowers

This is quite a simple one. Grab some carnations (or other white flowers), a vase, some food colouring and water. Add a generous amount of colouring to the water (20-odd drops), add the flowers, and wait. It can take longer than a day, especially if you haven't quite added enough colouring, so be patient. Here are some shots we took of our red and blue flowers (I reckon you can be more impressive than this!):



The flowers turned blue quicker than red for me, and others have seen similar things (anyone know why?)

The science on display is the capillary action of the water - that is, how the flower drinks even without its roots. This ability draws water against the force of gravity up the stem and into the petals. It works because the water evaporating from the petals and leaves of the plant "pulls" water up the narrow tubes in the stem (the xylem) to replace that which is lost. The tubes need to be narrow so that the combination of the surface tension of the water (caused by cohesion in the water - how well it sticks to itself) and the adhesive forces between the water and the walls of the xylem are strong enough to lift the water against the force of gravity. The adhesive forces are proportional to the diameter of the tube, whilst the weight of the water is proportional to this diameter squared - hence a smaller diameter favours the adhesive forces.

Something funky to try is to split the stem and put one half in blue and the other in red. You can get multi-coloured flowers.

Ep 156: Science for kids - home-made lava-lamp

This Christmas break, I have been mucking around with science experiments for my kids. Here is the first of a few easy experiments you can try at home.

The following videos show you how to make a home-made lava lamp. It is very simple - grab a clear cup (or bottle or vase or flask), fill it about a third full of water and two thirds full of oil. The oil floats on the water as it has a lower density. Add some food colouring (you can do this at the start directly to the water, or after you have added the oil - this has the added benefit of showing that the food colouring does not dissolve in the oil, so it drops through the lower density oil to the water below).

You may already have Alka Seltzer in your medicine cabinet - it is an over-the-counter pain reliever containing Citric acid and Sodium bicarbonate (also known as baking soda). Split the alka seltzer tablets into about 4 bits, and add them to make your lamp. See the videos below for what happens.

Shorter version:

Longer version:

The reaction that is occurring is:

Citric Acid + Sodium bicarbonate → Sodium citrate + Carbon dioxide + Water
C₆H₈O₇ + 3NaHCO₃ → Na₃C₆H₅O₇ + 3CO₂ + 3H₂O

Or more simply:
3H⁺+ 3HCO₃^-  → 3CO₂ + 3H₂O

Note, if you don't have alka seltzer, you can try baking soda, but add some vinegar to the original water mix, as vinegar is acidic and provides the H⁺.

When you add the alka seltzer to the water, the citric acid and sodium bicarbonate start to dissolve, which allows the reaction to start and is why they don't react in solid form in the tablet.

The reaction produces gaseous carbon dioxide, which has a lower density than both water and oil, and hence rises through the layers. When the gas bubbles exit the water into the oil, they trap and pull up a small amount of water with them. When the bubbles reach the surface, they burst and the water falls back through the oil. It's worth looking at this closely, as you will observe coloured water droplets that don't have quite enough CO₂ stuck to, or dissolved within, them to make it all the way to the surface, and so they float around, buffeted from side to side by other, more vigorously moving, droplets.

Here's some more over at CSIRO.

This is how you do optimisation

Press Release: Kellyville Ridge Man scores a perfect 15 in Opal

Kellyville Ridge NSW. Local resident Tim Surendonk is celebrating today after scoring the coveted perfect 15 in Opal. As Tim explains it, a perfect 15 occurs when a user of the Opal card pays the absolute minimum amount for unrestricted travel for 6 days in a week (Tuesday-Sunday).

The Opal rules allow unlimited travel after reaching 8 paid journeys, something which the average commuter will only attain after 4 days of to-work-and-back travel. You may think that this would be easy to do--just take 8 consecutive paid trips on trains, ferries or buses--but Opal rules make it difficult. Each trip must be separated by at least 60 minutes in order to qualify as a separate journey, and the day's paid journeys max out after $15 of expenditure--any trips after that aren't "paid-for" and so do not count towards the 8 trips.

Mr Surendonk managed his perfect 15 after carefully taking 8 minimum bus trips, each separated by at least an hour, paying $2.10 for the first 7 and 30c for that last trip.

"It wasn't easy", Mr Surendonk said. "I pretty much had to devote a whole day of annual leave to achieve it, but I did get to go to the Doctor and return some library books" he admitted.

To celebrate, Mr Surendonk took his kids down to Wollongong on Tuesday for a holiday outing. "I had to pay for them, but my trip was free! Thank you Gladys Berejiklian".

Mr. Surendonk's Opal Statement.

Thanks to Tim, PhD in logic, for writing his own press release! I work with some great folk. Tim did end up getting a letter from the minister congratulating him. More in the Rouse Hill Times.

Ep 155: Fact or Fiction with ANSTO

The Australian Nuclear Science and Technology Organisation undertakes research and development in nuclear science and technology. This has wide application including nuclear medicine, atmospheric monitoring, materials engineering, neutron scattering and climate change research.

ANSTO is also very active in science communication, and one of their major community engagement projects is Fact or Fiction, a 90 minute show where the audience watch clips of classic sci-fi hits before voting on whether the technology featured is actual science fact or pure science fiction. Once the audience voting has been conducted, an ANSTO scientist critiques the science featured in the film. They have also run a Fact or Fiction Survey, the results of which are illustrative of the general public understanding of science in everyday life. Another effort ANSTO is conducting is Neural Knitworks, where knitted neurons join together to create a textile brain installation.

I spoke with Rod Dowler from ANSTO's Discovery Centre about their science communication efforts, and in particular, Fact or Fiction. Listen to this show here:



In the podcast, we mentioned a song about hoverboards. I would have loved to have put it in the show, but that wouldn't be legal. So if you'd like to hear it, stream it  below or buy it from iTunes right here:





Songs in the podcast:

• Is Nuclear Power The Answer? - Karstenholymoly / CC BY-NC 3.0
• Sci-fi funeral - Asmus Koefoed / CC BY-NC 3.0
• The Unbroken Thread (The Molecules of Life Remix) - morgantj / CC BY 3.0

ABC Radio - June - Mars One

I've been doing quite a bit of regular radio with the ABC recently (ABC Riverina and ABC Central West), so I thought it would be a good idea to put up a post each month on what we've spoken about.

The main topic this month was the Mars One project, which plans to establish a permanent human settlement on Mars. This is an incredibly optimistic project, made even more interesting by the fact that it is going to be funded by a reality TV show, which will track the training and lives of the astronauts, and presumably follow them into space. A number of Australians are still in the running to be part of the final four who make it.



There are seemingly innumerable ethical issues with this project, notwithstanding the fact that at $6 Billion, it seems unbelievably cheaper than NASA estimates (~$100 Billion) for similar projects. Check out the company's FAQs - they have addressed a number of questions that immediately come to mind (food, air, fuel etc). The one outstanding question for me is - what if it goes wrong? Does the company abandon the astronauts on Mars? Does NASA have an obligation to go back to get them? What if everyone stops watching the reality TV show? I watched (well, glanced at) Big Brother One but can't tell you a lot about the following umpteen seasons...

One thing we do know is that long distance space travel is no place for extroverts. Unsurprisingly, a NASA-funded study has found that extroverts will probably drive their space companions bananas if kept in confirmed quarters for too long.

Some life analysis with Twitter

There was a great post recently on Flowing Data, The Change My Son Brought, Seen Through Personal Data. It got me thinking about what my life looks like through personal data, and probably the best source of data since the advent of smartphones is Twitter. Twitter recently made it possible to download your personal archive and it makes for some interesting analysis. Along with RSS feeds, Twitter is my major source of online news, education and entertainment, and it is also useful for personal communications and microblogging.

Downloading your personal archive is easy, but you need to do a little manipulation before you can play with it. My tweets were time-stamped in UTC time (I'm not sure why - perhaps by default, perhaps because of my location settings) so I had to adjust this for time zone changes due to day-light savings and overseas trips (I didn't bother with domestic trips as I don't have an easy record of them, and they don't make too much difference - an hour here and there).

The following has a dot for every tweet I've written since the end of 2010. Take note that the x-axis is quite long (3.5 years) and the dots are quite large (bigger than a day). I haven't annotated it, but it is interesting to spot life events - the birth of my children, various periods of leave and holidays, over-tweeting during The Ashes etc. There are auto-tweets that came out at the same time each week (which I've now stopped as they're annoying). There was a definite shift in the time I rise in the morning after December 2010 when my son was born and a surge in late-night tweets after my daughter was born in 2013.

Breaking it down is a little more interesting. The following shows tweet frequency for work days and non-work days (weekends, leave) since the start of 2013. On a work day, I tweet in the main on the train. I usually catch a train around 7 or 8am in the morning and the return train around 5 or 6pm. During work hours there is a trickle through coffee breaks and lunch, and after dinner is another peak. This type of profile aligns somewhat with the findings of other social media studies (Yellow Social Media Report – 2014 - thanks @problogger), although the amount I tweet on the train is more than the norm, whilst the amount I tweet at work is less (although it is a great way to horizon scan the various fields of science in which I work, once you follow the right people).

Non-work days follow a different profile, at least until after dinner. There's a slightly later rise in the morning, dips when we would be attempting to get out of the house, a dip at an earlier dinner time and a large peak in the evening once the kids are in bed. This peak is higher than a work day, in which time I might be preparing for the next day or falling asleep on the couch. By about 10pm it is basically the same till 6am the next day.

I'm posting this at about 9am on a weekend, having written it at about 10pm last night - that fits the curve pretty well. If you are a social media marketer (of which, at last count, there are 1,083,645,638 on Twitter), target my work trips (although I'm sure you know this from all that stunning big data analysis you do). The downside of this is that the train trip is too short to read anything of any length, which would explain why the 140 characters of Twitter spikes at these times.

Ep 154: Blogging, podcasting, royal jelly and using chocolate to determine the speed of light

Over the Easter break, I spoke with Lish Fejer on ABC 666 Canberra on her Experimentarium segment. We spoke on various things to do with science blogging and podcasting, and matters Easter related including:

• Royal Jelly (the Royals were in town, a great link if ever I've seen one),
• Determining the speed of light using your microwave and left-over Easter chocolate.

To learn more about Royal Jelly, tune into Episode 137: Can your environment change your DNA in which I spoke at length with Professor Ryszard Maleszka from The Australian National University’s College of Medicine, Biology and Environment about the molecular differences in over 550 genes in the brains of worker and queen bees that are a result of the queen bee eating royal jelly at a young age.

On determining the speed of light using a microwave, see the post Instascience by Tom Gordon in which he uses paper. We used chocolate and it worked pretty well, albeit very messily. You will enjoy trying this at home, and failing just gives you another shot! Note in the broadcast I mentioned that the speed of light was 2.97 x 10⁸ when it's actually 2.99792 x 10⁸ (please forgive such a grievous error...)

Listen to this show here - the audio is courtesy ABC 666 Canberra:


Here is a nicely produced video on how to do this - I started out making one and made a mess of my kitchen.

arXiv trawl: March 2014 - Astrobiology

This month's arXiv trawl brings us to astrobiology.

The Habitable Epoch of the Early Universe

In recent weeks, the world of cosmology has been buzzing with the news that gravitational waves - remnants of the Big Bang - may have been detected by the BICEP2 experiment. But did life come not long afterwards?

Abraham Loeb from Harvard University has posited in his paper The Habitable Epoch of the Early Universe that conditions were rife for life just 10 million years after the Big Bang. Life on Earth is about 3.5 billions years old, and it took about 1 billion years to first appear after the Earth was formed. So to think that life could have formed only 10 million years after the Big Bang - a blink of the eye in cosmological terms - certainly goes against conventional thinking.

To come to this conclusion, Loeb looked at the conditions needed for life to take hold. Astrobiologists talk of the Goldilocks zone - an orbit around a star where a planet is not too hot or too cold to have liquid water, just like here on Earth. On Earth, we are aided by an atmosphere that keeps temperatures mild. But there are other ways that a planet can stay warm enough for liquid water - tidal heating, for example, is thought to maintain a liquid ocean under the surface of Jupiter's moon Europa.

Loeb postulates another mechanism, one that I presume wouldn't be particularly good for your health if we could replicate it, but nonetheless would keep water in liquid form. In fact, he proposes that the whole Universe would have had these conditions. The cosmic background radiation is the afterglow of the Big Bang, fills the Universe and these days has a temperature of about 3K. But it wasn't always this cold, and moments after the Big Bang it would have had a temperature of billions of degrees (more actually). It has been cooling since then, and around 10-17 million years after the origin of the Universe, the cosmic radiation would have made the Universe nice and balmy with liquid water.

But even if the temperature was right, is 10-17 millions years long enough for rocky planets to form on which life can live? And were there enough heavy elements around to get the chemistry of life going? Loeb thinks maybe. Matter was pretty evenly spread around the Universe at this age, but some areas would have been more dense than others. Where the matter was more or less dense than the average, this is called a perturbation. Assuming these perturbations had a Gaussian distribution (the classic bell-shaped normal distribution), massive stars of Hydrogen and Helium could have formed at the very edge of the distribution - 8.5 standard deviations from the mean. This is pretty unlikely; if you've done management courses you'll know that 6 standard deviations from the mean (that is, Six Sigma) is what you are aiming for when detecting defects. If you're making a product, a Six Sigma event would happen roughly every few hundred million products. A 8.5 sigma event would occur less than once every few hundred trillion products.

What this means is that if the density of the early Universe had Gaussian perturbations (and it's not settled science that it did), it's not very likely such stars could have formed and in the process created heavy elements, but the Universe is a big place!

Imagine then that there were rocky planets formed from exploding first generation stars that contained the elements of life in this temperate Universe. Could there be life? 10 millions years is not a long time for life to form - it took a billion years on Earth, and then longer to evolve. But let's say it did. Could it still be out there? Well, the issue with having cosmic radiation as life's heat source is that it cooled down over time and when the Universe was 17 million years old, it wouldn't have been warm enough for liquid water. So the planets on which life resided needed to have their own heat source, and then perhaps life could have escaped through panspermia. Loeb recommends that astronomers look for biosignatures in really old stars to further investigate, something that is now technically possible as we discover more early generation stars.

Loeb also makes a more philosophical point. Some proponents of the anthropic principle claim that various fundamental physical constants are what they are - some say "fine tuned" - because they must be those values to bring about life. Loeb argues that anthropic arguments are weak, at least with regards the cosmological constant, which describes the density of energy in the Universe, as this habitable epoch would have existed for various values of the constant.

I was actually going to post a few other astrobiology arXiv papers, but I think this is enough for one Saturday! I'd be interested to hear what others think of this idea that life could have existed so early in the Universe's life.

References:

1. Abraham Loeb (2013). The Habitable Epoch of the Early Universe arXiv arXiv: 1312.0613v2

Copper Nanotubes

It's not often a chemistry journal article will make you laugh out loud. From Structural and electronic properties of chiral single-wall copper nanotubes - enjoy.

Abstract:
The structural, energetic and electronic properties of chiral (n, m) (3⩽n⩽6, n/2⩽m⩽n) single-wall copper nanotubes (CuNTs) have been investigated by using projector-augmented wave method based on density-functional theory. The (4, 3) CuNT is energetically stable and should be observed experimentally in both free-standing and tip-suspended conditions, whereas the (5, 5) and (6, 4) CuNTs should be observed in free-standing and tip-suspended conditions, respectively. The number of conductance channels in the CuNTs does not always correspond to the number of atomic strands comprising the nanotube. Charge density contours show that there is an enhanced interatomic interaction in CuNTs compared with Cu bulk. Current transporting states display different periods and chirality, the combined effects of which lead to weaker chiral currents on CuNTs.

References:

• Duan, Y., Zhang, J., & Xu, K. (2014). Structural and electronic properties of chiral single-wall copper nanotubes Science China Physics, Mechanics and Astronomy, 57 (4), 644-651 DOI: 10.1007/s11433-013-5387-8