How small can something be and still have a shadow?

photo by asilverthorne - public domain

My five-year-old daughter asked this question.  There must be some lower size limit at which you just can’t cast a shadow, right? 

Not necessarily.  As it turns out, you can be really any size and still have a shadow.

All it takes to make a shadow is to block light, and since light is made of photons (basically, consider them the particles that make light waves,) I figure all you technically have to do is keep photons from going through you and – ta-da! – shadow!

Photons?

For my shadow-making purposes, I’m just dealing with whether at least one photon gets knocked off course.  But, it should be noted that light, among other quantum entities, is a particle and a wave at the same time, as was figured out with the classroom-famous double-slit experiment.  Recently, some intrepid scientists at a Swiss university photographed light in both its forms simultaneously.  An article and animated video of how they did it can be found here.

Using the naked eye…

The smallest shadow that you can see would be made by whatever object is so small that you can barely see it, so if you’re, say, me, the smallest visible shadow would be from maybe a grain of sand about the size of this period here.

Using some serious tech…

Some scientists at an Australian university made a bit of a splash when they photographed the shadow made by an atom using only visible light and an extremely powerful optical microscope.  

Says Professor Dave Kielpinski of Griffith University's Centre for Quantum Dynamics:  "We wanted to investigate how few atoms are required to cast a shadow and we proved it takes just one. We have reached the extreme limit of microscopy; you can not see anything smaller than an atom using visible light.”

Check out the atom shadow right here.

Using my basic definition…

And coming at it from the particle physics realm, you could actually be no size and still block a photon and therefore have a one-photon-sized shadow.  That is, if you’re something like an electron.

Electrons are so teeny that physicists consider them to just have no size.  Basically, they’re a one-dimensional point for all intents and purposes, and mathematics involving electrons work out just fine if electrons are sizeless and referred to as a “point particle.”

Handily, photons are similarly teeny, all energy and no mass (like the toddlers of the quantum world perhaps?), which means they go and go at the speed of, well, light, until something stops them.

But point-like as electrons may be, they still don’t usually let photons pass right through.  It's hard to tell because of the wave nature of all parties involved, but we're quite certain that photons can collide with electrons enough that diagrams are made to commemorate the moments. 

When photon meets electron, they can collide with a variety of results, including the creation of totally different particles, but always with some change in energy and trajectory.  Regardless of what exactly happens, it would be rare indeed for you to find the photon continuing on its initial path once a collision has occurred, so technically, the photon didn’t land behind the electron, and therefore – ta da! – shadow!

If this all sounds a little too far-fetched and you need some better insight, ask the Shadow.  He knows.  J

What would happen if you cooled a Skittle down to absolute zero and hit it with a hammer?

photo by StockSnap  - public domain 

Because inquiring eight-year-olds want to know!

Before we proceed, a few definitions –

A Skittle is an M&M-looking candy-coated chewy sugar rush, for which you may have heard the ad campaign, Taste the Rainbow, or the more evocative Experience the Rainbow. 

(By the way, put a Skittle or M&M in water and watch the coating dissolve except for the “S” or “M” which floats to the top.  Yum!)

The hammer we mean is just the basic clawed type you have in your toolbox for bashing nails, thumbs and absolute zero Skittles.

Absolute zero is presumably as cold as something can be, and warrants a little further explanation than the former two ingredients.

Dude, that is cold.

photo by moritz320 - public domain

Zero degrees Celsius is where water freezes, zero degrees Fahrenheit is where I don’t let my kids go outside for very long, and zero degrees Kelvin is absolute zero -- where molecules stop moving around.  (Quick review – under normal circumstances, molecules are always moving around.  Faster in gases, slower in solids, but we haven’t seen ‘em actually hold still yet.)

Now, absolute zero is not the complete absence of all movement.  The super-frozen molecules don’t move, but the particles within the atoms that make up the molecules are still moving around in their usual way, just in their ground state.  An atom’s ground state is its lowest-possible energy state, so basically the electrons are being as chill as they can be, but they’re still zinging around in their dizzying dance of quantum probability (which we’ll mess with later on.)

Scientists have gotten some substances to within spittin’ distance of absolute zero, and when things get that cold, they often exhibit bizarre behaviors, such as becoming superconductors (having no electrical resistance) or superfluids (flowing without viscosity.)  Helium superfluid can flow in an endless fountain, and superconductors’ magnetic fields can cause levitation. 

So could you super-freeze a Skittle?

photo by Heamer - public domain

Getting complex molecules down to nuthin’-Kelvin is very tricky.  So far, gases have been the best candidates. 

Researchers at MIT got some sodium potassium molecules down to almost zero Kelvin, but they had to assemble the molecules from their constituent atoms as they went along.  They found, though, that the super-cold molecules were stable, long-lasting, and showed electric charge imbalances that could produce a magnetic effect between molecules.

Professor Martin Zwierlein of MIT says that “with ultracold molecules, you can get a huge variety of different states of matter, like superfluid crystals, which are crystalline, yet feel no friction, which is totally bizarre. This has not been observed so far, but predicted.”

Perhaps a Skittle would be a candidate for a superfluid crystal, if the crystalline structure of sucrose would play any part.  Figuring that a Skittle is mostly sugar, we’re looking at a bunch of these molecules:

12 atoms of carbon, 22 atoms of hydrogen, and 11 atoms of oxygen (C12H22O11)

-- a far cry from the two-atom item (NaK) put on deep freeze at MIT.

Another group of scientists from the University of Colorado found that their ultra-cold potassium rubidium (KRb) molecules flew apart upon collision, so perhaps our Skittle would need some sort of containment to keep it intact until the hammer hit.

So it’s hard to say for sure if our absolute zero Skittle would just fall apart, become some superfluid soup of sugar components, or be hard as a rock.

So hit it with a hammer, already!

photo by jackmac34 – public domain

We did put a Skittle through a test run with a household freezer and a household hammer, and in that case, it shattered admirably into many non-uniform shards.

Our best guess at this point is that if a Skittle maintained its cohesion through the cooling process, the hammer hit would raise the temperature at the moment of impact by making the molecules move, and would probably result in a very pulverized Skittle.

Unless said Skittle became an exotic state of matter first and ascended to a realm beyond the mundane friction a hammer would produce.  You could have superfluid crystal Skittle, or ether-Skittle or plasma-Skittle or pile-of-atoms-that-used-to-be-a-Skittle -- just as elusive to experience as an actual rainbow.

…Fade to black.  “That concludes the regular physics version of the answer.  Thank you for reading.  Feel free to go home and freeze a Skittle.  Or…read on…”

Absolute Zero Skittle: the Quantum Theory Fun Part

photo by geralt – public domain

MIT’s Professor Zwierlein also said, “We are very close to the temperature at which quantum mechanics plays a big role in the motion of molecules, so these molecules would no longer run around like billiard balls, but move as quantum mechanical matter waves."

Now we’re talking!

You see, quantum particles exist under a slightly different set of rules than we big huge visible solid-looking things.  Those teeny pieces move in such a way as to function as both particles and waves, kind of fuzzy in their location, as if occupying many spaces at once while moving too fast to be captured on film – physicists generally determine their “location” by figuring out the probability of where they most likely might be.

So let’s get theoretical with our Skittle. 

As stated before, absolute zero is the state of having chilled-out molecules but their constituent atoms still have energy; the atoms are just in their ground state.  Let’s see what might happen, according to the chalkboard, if we slowed down our Skittle until even the subatomic particles were not moving.*

There’s an odd and seemingly true (as far as we can tell) feature of quantum physics called Heisenberg’s uncertainty principle, brought to us in 1927 by theoretical physicist Werner Heisenberg.

Heisenberg wrote: "It seems to be a general law of nature that we cannot determine position and velocity simultaneously with arbitrary accuracy."

The uncertainty principle is general acknowledgment that we just can’t make a precise statement about the where and where-to of a fundamental particle; it’s exact position and state of motion (momentum) cannot be simultaneously defined.  Kinda goes with the fact that a probability is as close as we get to pinpointing, say, an electron.  And even though it’s meant to be an observation of an apparent limitation, the principle exists as a math formula.

The actual equation for the uncertainty principle is apparently pretty uncertain itself, if you survey the internet, so we’re going to go with Stanford University’s take on it, as explained in the Stanford Encyclopedia of (get this) Philosophy (quantum physics kind of belongs in the philosophy circle, after all) right here!

This is why our Skittle is weird:   δpδq ∼ h

…where δp = indetermination of particle's position, and δq = indetermination of particle's momentum, and h = Planck’s constant, which is 6.626 x 10-34 joule seconds (i.e. a super teeny number.)**

So if just for fun we treat Heisenberg’s relation like a straight-up math equation rather than a general statement about how much we can’t know, we can figure this:

If all motion stopped, that is, if even the subatomic particles held still, then the range in error of momentum (δq) would be zero because its movement (i.e. lack thereof) would be absolutely known, and then the range in error of position (δp) would have to make up for it by becoming infinite.

Or as Heisenberg put it: "In a stationary state of an atom its phase is in principle indeterminate."

Or as physicist Kenneth Ford explains: “Carried to a limit, it even means that if you knew one quantity precisely, with perfect exactitude, there is another quantity about which you would know nothing.”

Or as I put it: a Skittle at absolute-NO-motion-zero could be… anywhere.***

Experience that theoretical rainbow!  Then smash it with a theoretical hammer.

*I care not that this is impossible by all accounts. 

**Planck’s constant is a teeny number that’s proven to be super useful in equations dealing with particle physics.  A semi-related and similarly teeny number is the Planck length (about 10-35m,) which has been described thus:

The number of Planck lengths that could be lined up across a proton is comparable to the number of protons that could line up from Philadelphia to New York!

I just had to share that.

***Yeah, yeah, it wouldn’t really happen that way… even when working with probability within the uncertainty principle, you still have borders of sorts, like the quantum Skittle would be mostly under the hammer and not all hanging out in Morocco and Proxima Centauri…but as we say in particle physics and astrophysics, “the math works out!”

The Brains of Squiggly Creatures

In researching brainless animals and while studying up on worms for a second-grade classroom project, I came across some intriguing notes regarding the brain situations of a few squishy creatures, all worth sharing!

photo by Pixabay user "blickwinkler"

Earthworms

The part of a worm considered the brain lies above the throat, sort of in the head like ours, and then connects to the first blob of neurons in the worm’s body-length nerve cord.  That first neuron collection is called the first ventral ganglion – that is, the first neuron cluster that doesn’t count as an official brain, located at the belly / ground level of the worm. 

The funky thing is this – if the worm’s brain is removed, the worm never stops moving.  If the first ventral ganglion is removed, the worm forgets to dig or eat.  So a worm can get on just fine for a while sans brain, but would probably eventually exhaust itself. 

So if you want to tell someone they have the brain of a worm, you’re implying that they’re fairly versatile and can actually control themselves.  And if you want to sound erudite when you do it, say it like this: “Habes cerebrum vermis!” (or say it while waving a stick at someone to come across as a serious Harry Potter fan.)

photo by István Asztalos

Leeches

These squooshy, mostly water dwelling bloodsuckers are actually full of brains!  The leech’s body is made up of 32+ segments, the front four serving as a head with a sucker mouth and a leechy brain.  Next come 21 segments, each with their own neuronal ganglia – basically a mini brain for each segment.  Finally, the last seven sections make up the sucker tail and have a posterior brain directing traffic from that end.  You might say the leech is a long, slinky bag of brains.

If you desire to devour a scientific paper about all this, go here.

 “Habetis cor hirudinea!”  (“You have the brains of a leech!”…a compliment, perhaps, or another really weird Hogwarts spell.)

 

photo by Pixabay user "Josch13"

Caterpillars

Our last squiggly creature of brainy note is the caterpillar, raised to worthy status as a mentally competent invertebrate by virtue of its surprising capacity for memory.  Some intrepid researchers at Georgetown University conducted a study in which they discovered that moths actually retained memories of things they had learned as caterpillars.  As with humans, apparently, memories gained early in life faded before adulthood.  But conditions present for the caterpillars closer to their cocooning time appeared to be remembered after the larvae emerged with wings.

This feat of memorization is impressive because, well first of all, they’re squiggly creatures, but also because caterpillars essentially liquefy in their cocoon and then coalesce into moth or butterfly form.  There’s a neat description of the process by Scientific American here, which kicks off the description of metamorphosis thusly: “First, the caterpillar digests itself, releasing enzymes to dissolve all of its tissues.”  Ew!  That those caterpillars can retain memories through a process that’s even remotely like that is totally amazing.

“Dare diploma a tinea!”  (“Give that moth a diploma!”…or as near as I can get with Google Translate.)

 

                          “Ya’ll remember what to pick up at the store when you can fly there, right?"

photo by Pixabay user "GLady"

 

Which animals do not have a brain?

You need a brain to live, right?  Nope!  Well, you do, but there are a fair number of Animal Kingdom cousins who don’t.  Let me introduce you to some of them!

Photo by Daniel Battershell

 

If I only had a brain…

First, a quick definition of what kind of thinking organ we’re looking for. 

The thinking that happens in our brain (conscious and otherwise) is carried out by neurons – nerve cells that process information by sending signals wherever they need to go.  A bunch of neurons gathered together directing traffic as part of the central nervous system is considered to be a brain.

A bunch of nerve cells clustered together is called a ganglion, and if it’s part of the peripheral nervous system (as opposed to central) then it’s not officially a brain.  (As a note, part of our brain is called the basal ganglia, but it’s argued that this region should be called the basal nuclei to be less confused with non-brain ganglia.)

Regardless, while some of the animals on our list may have ganglia controlling some of their functions, most of the animals here don’t even have any ganglia at all!

 

Tunicate

Commonly known as the sea squirt (that’s the cutest name!), this marine filter feeder looks and functions like a blobby straw.  It’s been around since the Cambrian Period, so it has done well for itself without a brain.

But get this – only the adult sea squirt has no brain.  A baby squirt, which is a tadpole-looking larva, actually has a tiny brain and one eye, and it can swim around but it can’t eat.  When the juvenile gets hungry enough to become a grown-up, it finds a place on the ocean floor to settle in for a filter-feeding and stationary adult life.  Once rooted, the baby squirt grows and absorbs all the parts it no longer needs, including its tail, eye, and brain!  These useless bits turn into new parts as the sea squirt becomes fully grown…and brainless.

Trichoplax adhaerenes

This creature is only a millimeter wide and it sucks up food with its underside, so we’re going to give it a break and totally excuse it for not having a brain.

This creature doesn’t have a cute nickname as of yet, but the phylum name (placozoa) means “flat animals.”  So far, trichoplax is the only species in the phylum, but we may discover more species in there as we look more closely down the road.

Trichoplax looks like a teeny, grayish, almost transparent, shapeshifting pancake.  It also needs a cute name.  Squirmy Cake, perhaps?



Photo by Bernd Schierwater …of a squirmy cake

Echinoderms

These are our good friends the sea stars, urchins, sea lilies, and sea cucumbers.  A few have ganglia, but nobody here has an actual brain.  There’s no planning ahead in the echinoderm’s daily life.

Sea lilies are rooted to the ocean floor and gather food via their five pairs of feathery arms, no thinking necessary.  The others, like the urchins, creep around looking for their food.

Sea stars have no ganglia at all, yet they have some sense of touch, smell, sight, and so forth.  Apparently, if one of the sea star’s arms smells something good, it stages a coup over the other arms’ initiatives and starts pulling the creature towards the food source. 

Sea cucumbers may be brainless, but their defense mechanisms are genius.  They can disgorge their guts and internal organs, startling and grossing out a would-be attacker.  They also can eject long sticky tubes from their anus which can ensnare and permanently disable a predator.  Disgusting but effective, which seems pretty smart to me.

Jellyfish

Instead of having a brain or even ganglia, jellyfish manage to get their business done by virtue of a neural net – a system of connected neurons interwoven around the animal’s body.

Like the humble squirmy cake, jellies can be 1 mm wide …but the big ones can get you with 100-foot-long tentacles, and some of the little ones can kill you with relative ease, so brain or not, it’s best not mess with that whole phylum.

Corals and Anemones

Like the jellies, corals and anemones lack a centralized nervous system and instead have a neural net of sorts initiating movement around the body as needed.

By the way, sea anemones, corals, and jellyfish have all digestive chambers with a single opening, which serves as both the mouth and the anus.  Just thought I’d share that.  (And put these on the list of things I’d rather not be reincarnated as.) 

Sea Sponge

Perhaps the most famous for not having a brain, the sea sponge doesn’t even have a digestive, nervous or circulatory system.  Instead, it has a bunch of unspecialized cells that can migrate around the animal’s body and transform into whatever type of cell is needed at the time.  How cool is that? 

And check it out – sponges can sneeze.  And while our human sneezes are fleeting, a sea sponge sneeze can last for 30 to 60 minutes!  This impressive feat is explained in an article here which notes, “Sponges are the only multicellular animals without a nervous system. They do not have any nerve cells or sensory cells. However, touch or pressure to the outside of a sponge will cause a local contraction of its body.”

Bivalves

These are your clams, oysters and mussels, which don’t have brains but do have ganglia, so in the company of all these other brainless creatures we can go ahead and give the bivalves some little graduation caps.

Honorable Mention for Slime

Slime mold is not a member of the Animal Kingdom and so can’t be included in this list, but it deserves mention in the annals of brainless function because, according to a study by the University of Sydney, this mold has memory!

This single cell organism leaves a trail of slime to tell where it’s been, and research has shown that slime mold is capable of anticipating periodic events and even solving mazes.  Biologist Chris Reid admits, "I, for one, welcome our new gelatinous overlords."

Google googol for lots of 0s

photo by Gerd Altmann

Kids around here recently celebrated their 100^th day of the school year by partaking in various activities revolving around the number 100.  In honor of that auspicious event, we are checking out what happens when you get 100 zeros to play follow-the-leader with a 1.

Googol!

In 1938, mathematician Edward Kasner was searching for a name for a number he had in mind to illustrate the thought-level difference between infinity and numbers that are not actually infinite but just seem to go on forever by virtue of being ridiculously huge.

The number he envisioned was 1 followed by 100 zeroes, which you can either write all the way out, or express like this: 10¹⁰⁰.  But what to name this crazy big number?

As Kasner was out on a stroll with his 9-year-old nephew Milton Sirotta, he asked the youngster for an opinion.  Milton – proper purveyor of nine-year-old wisdom (don’t underestimate it!) – thought that a pretty ridiculous number should have a funny-sounding name, so he fatefully suggested “googol.”  And it stuck.

How big is that, really?

Let me tell you, googol is big.  Googol is greater than the number of atoms in the known universe.  If you labeled the universe’s subatomic particles with sequential numbers, you’d run out of matter bits before you got to googol.

If you started counting by ones at the moment of the Big Bang and spoke one number per second from then until now, you would only be about halfway to counting to googol.

Be glad for that big number, though, for around googol is the number of years we expect to pass before the heat death of the universe -- a ridiculously long existence expressed by a ridiculously large number.

But googolplex knows what from big!

Young Milton went on to suggest an even bigger number – googolplex – which he described as writing a 1 followed by zeroes until you get tired of writing.  Kasner thought there should be a little more definition there, but googolplex ended up being plenty big indeed – it’s defined as a 1 followed by a googol of zeroes.

How much is a googolplex?  I’ve seen it described thus: take the universe and pack it full with specks of dust.  Give each speck a number assignment (1, 2, 3, etc.).  Now reassign each speck a new number.  Keep going…the amount of different numbering combinations you could get out of a speck-stuffed universe is approaching the range of a googolplex.

How about Google?

Word has it that the search engine giant got its name during a meeting when its founders were brainstorming and looking for available domain names.  To give an impression of the company’s hoped-for far-reaching web presence, someone suggested “googol,” and the person typing in potential domain names typed “google” – presumably just an outright misspelling – and that’s where Google comes from. 

Similarly the folks at Google thought it would be cute to call their headquarters the GooglePlex.  Yeah, it’s cute.

And finally…

There’s a video here that reviews all this and then shows how a universe that’s googolplex meters wide would be so big that the subatomic particles would run out of possible arrangements of themselves before running out of space to arrange in, and would therefore have to repeat some permutations exactly, resulting in your ability to have tea with yourself…if you could find yourself in a googleplex-meter-wide universe, that is.

Which extinct animals could be cloned right now?

photo by Nancy Steffens

This question draws forth images of children heading off to school each morning, riding on their saber-tooth cats, pet moas stalking along behind, dodging roaming mammoths along their way.

What is cloning, really?

Cloning is a process that makes genetically identical copies of an organism.  There is such a thing as natural cloning – this occurs with some plants and single-cell organisms which copy themselves without fertilization, and identical twins are also natural clones.  As for artificial cloning, there are three basic types – gene, therapeutic and reproductive.

Gene cloning makes copies of genes or DNA, and therapeutic cloning makes stem cells for creating new tissues.  But here we’ll be talking about reproductive cloning -- the method by which an animal can be created from material cells, such as those from skin and hair. 

The basic process is this: an egg is taken from a living animal and the cell’s nucleus is removed.  To review, the nucleus is where the DNA hangs out, which instructs the cell as to what to do with itself.  Then a cell is taken from the animal to be cloned, and its nucleus is removed and put into the host egg.  This is done either by just sucking it out with a syringe and inserting it into the egg, or by joining the two with an electric pulse.

Now you have a living animal’s egg containing a nucleus from another (could be dead) animal.  The egg is spurred into action with electricity, and after it grows to embryo size in a lab, it is placed into the womb of a related species. 

There’s a handy illustrated fact sheet about the process here.

Now you could have a kitten growing in Cat C that came from the egg of Cat B and a skin cell of Cat A.  Or a saber-tooth baby going for a ride in a lion.  Or even a Tasmanian tiger, the genes of which have been made to be produced in the fetus of a mouse -- not that the mouse in this case carried a tiger to term, but it illustrates that you don’t need to have the same kind of animal to recreate age-old genes.  Surrogate mothers for full-term, fully-formed creatures should, however, be at least somewhat related to the original species.

So thanks to the existence of elephants, we could find a surrogate mother for a mammoth, and recreating the passenger pigeon via a rock pigeon’s egg would be easy (as easy as cloning is, that is.)  But the lack of availability of a suitable womb would postpone the de-extinction of some species, notably the giant ground sloth, which will have to wait for an artificial womb because its closest living relative – the 8-kg two-toed sloth – would have a mighty hard time birthing a 1,000-kg ground sloth baby.

As for animals that have no existing relatives, there is still hope.  As recently as 2007, a method was found for reverting adult cells into embryo-like stem cells, which could then be made to produce any kind of tissue call.  So finding an egg to host is not necessarily necessary, but the technology still has a ways to go before it becomes particularly efficient.

Does it work?

Most of the time, actually, no.  Cloning has a very low success rate compared with good ol’ regular reproduction.  The first animal successfully cloned from an adult cell – the famous Dolly the sheep, born in 1996 – followed 276 failed attempts. 

While cloning from adult cells of living creatures has gradually gotten more successful, the overall baby production process is still way less efficient than letting the animals reproduce naturally, not to mention that clones have a higher propensity for health problems than non-clones. 

So as far as, say, producing livestock, cloning makes no sense.  But in the case of extinct animals, it is the only way.

So whose DNA do we actually have available to clone right now?

Creatures that died off more than a few tens of thousands of years ago are gone for good; their DNA has broken down by now.  However, animals that have gone extinct during or after the last ice age stand a chance if some of their tissue was preserved.  Ice-age creatures have been found preserved in -- no surprise -- ice, as well as tar pits, and animals that died more recently have been collected by curators of museums and labs.

The San Diego’s FrozenZoo has cells from over 1,000 different species, including critically endangered species like the northern white rhino.  Around the globe, cells are on hand that could possibly be reborn into a number of extinct species, including the recently extinct Tasmanian tiger and passenger pigeon, the giant moa, the Irish elk, and yes, saber-tooth cats and mammoths.

Also in the lineup for de-extinctable species are – ready for this? – Neanderthals.  Recent evidence has suggested that those beefy cave-dwellers were actually much more intelligent and articulate than previously believed, and it turns out that they’re not so separate of a species from us after all.  In fact, interbreeding certainly occurred, and still does, sort of – it so happens that a lot of us have Neanderthal DNA in us right now!  My own uncle recently got confirmation that he’s 2% Neanderthal, so I guess I’m in the club.  Does that explain why I lumber around so much before I get coffee?

 

Has anyone brought an extinct species back?

Yes, indeed – but sadly, not for long.  In 2003, scientists cloned a Pyrenean Ibex, the first to exist on Earth since the species’ presumed extinction in 1999.   Unfortunately, the youngster died soon after birth from a malformation in its lungs.

Still, hope is in the air, and plans are ever afoot to clone lost creatures, especially the iconic mammoth.  Japan’s Dr. Akira Iritani claims he will produce a mammoth by 2016…which is pretty optimistic, considering the general failure rate and the fact that the critter will have to gestate for a good year and a half at least.

It seemed like a good idea at the time

So should we really be doing this?

When faced with the question of whether the dinosaurs in the movie Jurassic Park should exist, Jeff Goldblum’s character Dr. Malcolm says, “Your scientists were so preoccupied with whether or not they could that they didn't stop to think if they should!”

There are those who believe that we owe resurrection to creatures that humans drove to extinction.  This excerpt from a NationalGeographic article shows the stance nicely:

“If we’re talking about species we drove extinct, then I think we have an obligation to try to do this,” says Michael Archer, a paleontologist at the University of New South Wales who has championed de-extinction for years. Some people protest that reviving a species that no longer exists amounts to playing God. Archer scoffs at the notion. “I think we played God when we exterminated these animals.”

There is also the belief that we should carry on with cloning because, well, we can.  As Insung Hwang of the Sooam Biotech Research Foundation says, “The thing that I always say is, if you don’t try, how would you know that it’s impossible?”

Some reasons to reconsider just up and cloning everything include concern about the survival of the animals once they’re back on Earth.  For some species, their former habitat is greatly reduced or entirely unavailable.  Alternately, some species whose habitat is intact may pose a threat to the ecosystem that has established itself since the animals’ departure, making the extinct species now an invasive one.

Others believe that resources would be better spent focused on the preservation of existing endangered species.  Cash goes a lot further in environmental preservation efforts than it does in the realm of low-success-rate cloning.  Proponents of the focus-on-the-now crowd also see cloning as better used to preserve tissues and attempt to clone living endangered animals before working on those that are already extinct.

The seven-year-old who brought up this question thinks that science should certainly try to clone some extinct species, but cautions against reviving the “dangerous” species of the past.  “Wooly mammoths could be stomping on and destroying everything…and saber-tooth tigers would do damage to alive creatures.”  I can see some wisdom in that.

Truth, bro.

But really, pros and cons aside, wouldn’t it just be neat to see some ice age megafauna cruising around in the flesh?  Hank Greely, a leading bioethicist at Stanford University, agrees:

“What intrigues me is just that it’s really cool,” Greely says. “A saber-toothed cat?  It would be neat to see one of those.”

Especially if we could ride it to school.

“How can there be a start without a beginning?”

Here is the conversation that led up to this question:

Seven-year-old kid (coming from a pile of LEGOs, looking concerned): “I’m all mixed up.”

Me: “How so?”

Kid: “In order to start, you have to have a beginning.  But how can you start when there’s no start?  Everything has to have a beginning!  How do you start when there’s no beginning?!”

Me: “Is this about building a Lego robot or is this about the existence of the universe?”

Kid: “The existence of the universe.”

I reassured the worried youngster that his was a question that has been pondered by human beings ever since human beings could ponder, and that, frankly, we don’t know how the universe began.  We do know that it’s a really big question.  We also debate whether it’s relevant to our daily lives (short of the relevance in that it, apparently, happened.)  But relevant or not, answerable or not, we humans forge on to find out, and there are always some reigning theories.

Photo from WikiImages

The Universe Begins: Bang!

The currently prevailing model regarding the beginning of the universe is, of course, the Big Bang theory.  The idea is that everything started out as a singularity – that is, a single point containing all the matter that now comprises the universe.  There was no space or time yet, just that little dot of everything, with all four fundamental forces (electromagnetic, gravitational, strong and weak) combined as one (hey, maybe that was the Force!)  The dot blew up and expanded outwards, creating the universe as we know it.

The problem with this theory, math-wise, is that Einstein’s theory of general relativity – which works so well at explaining and predicting how the universe behaves – doesn’t work at the actual point of the singularity.  Quantum physicists are working on that (more on that later.)

The Universe Begins: Bounce!

There’s another idea out there that describes the universe as continually expanding and contracting down to almost a point, then bouncing back outwards again.  As explained by one of the authors, James Hartle, the universe “collapsed from a previous large phase, bounced at a small but not zero radius, and expanded again to the large phase we are living in.”

This theory doesn’t work perfectly well, math-wise, either, which the study authors readily admit.  As Hartle says, “our model does make a number of strong assumptions…this is a standard trade-off in physics.”  So far the math indicates “a good chance” – yea, a “significant possibility” that the universe started out with a bounce.

The Universe Begins: Splat!

The “big splat” theory (formally known as the ekpyrotic scenario) fits in with both big bang and big bounce theories, but has an explanation for what got things going in the first place.  The idea is that, rather than starting as a singularity, the universe rose to existence from the collision of two branes (or as quantum zombies would say, braaaaaanes!)

Part of string theory, branes are basically objects that can exist in various dimensions.  The term “brane” comes from “membrane,” the term for a two-dimensional brane.  Branes exist under the auspices of quantum physics, and they hang out and multiply anywhere/when in spacetime.  According to Paul Steinhardt at Princeton University, branes collide every trillion years or so.  When they do, they essentially destroy and recreate the universe.

The Universe With No Beginning

A new universe origin story has recently been proposed, which attempts to marry somewhat the relativity and quantum camps.  As Ahmed Farag Ali of Benha University says, “Our theory serves to complement Einstein’s general relativity, which is very successful at describing physics over large distances...But physicists know that to describe short distances, quantum mechanics must be accommodated."

Applying quantum corrections to the Raychaudhuri equation (which deals with the motion of matter in close proximity) and fitting the whole thing in with the theory of relativity, the result suggests that the Big Bang didn’t happen and the universe has just always been around.  And always will be.

 

So how do you start with no apparent beginning?

Well, as it applies to we humans making things happen, we make those beginnings by, well, starting.

Here’s what some sages have to say about it:

“The beginning is the most important part of the work.”  ~Plato

 "There are two mistakes one can make along the road to truth…not going all the way, and not starting."  ~Buddha

“The way to get started is to quit talking and begin doing.”  ~Walt Disney

“Start where you are. Use what you have. Do what you can.”  ~Arthur Ashe

“Try not. Do, or do not. There is no try.”  ~Yoda

“Just go!”   ~Me, when it’s time to go

The Final Word...

…goes to the kid who started all this.  He ponders: “There might have been something that grew to fit space.”  He questions: “What was before the universe?  If there’s something more out from the universe, what is it?  It’s not nothing!”

He mulls it over: “I don’t think there was any start of everything.  But there had to be a start of everything.  How can there be a start without a beginning?  There would have to be a beginning!”

He concludes: “If you’re getting confused about this, throw away the word ‘beginning.’  Then you wouldn’t think there would be a beginning.”

Well that’s a start.