power of ten - nccr must :: nccr must1018s formation of structures in the universe – 13.8 ga zbox...
TRANSCRIPT
Power of Ten A journey through -me
Jürg Osterwalder, Anna Garry, Thomas Feurer
Philosophy
Relevant to MUST
Information (enough to trigger kids to look for
more)
A piece of art (trigger kid’s curiosity)
Concept
• Rela-ve and not absolute -me scales (an event takes 30 years, and not started 30 years aCer the big bang …) • Keywords:
• Molecules relevant to human life (water, proteins, …) • Human organism (seeing, hearing, cells, protein and enzyme func-on, …) • Human environment (universe, milky way, earth, …) • Things relevant to MUST (light, math, computers, …)
What to do
• Go to the poster and pick the -me scale you (and your colleagues) want to work on • Put a s-cky note on the poster with the following informa-on:
Name: Email: Group / Professor / PI:
Timescale:
What to deliver
1. A series of 10 images (remember the images must be original) 2. A -tle and a short text explaining the sequence of images. 3. Short explana-on of keywords and useful links 4. Provide at least one trustworthy reference confirming the -me scale
Deadline:
March 10th
Book design
Sabina di Fa]a, Agence Symole, Fribourg
Formation of Structures in the Universe – 13.8 Ga 1018 s
zBox supercomputer simulation, UZH
zbox supercomputer simulation, UZH (Rok Roskar, Romain Teyssier & Ben Moore)
The sequence shows the forma-on of the large scale structure of the universe. A fixed co-‐moving volume of the universe is shown that is 3x1023 m across today (therefore smaller in the past). It shows the total mass distribu-on colored according to its density – it includes dark ma]er and stars and gas. This region would form a massive cluster of galaxies – the largest structure in the universe.
The ages of individual stars in the Milky Way can be es-mated by measuring the abundance of long-‐lived radioac-ve elements such as thorium-‐232 and uranium-‐238, then comparing the results to es-mates of their original abundance, a technique called nucleocosmochronology. These yield values of about 12.5 ± 3 billion years for CS 31082-‐001 and 13.8 ± 4 billion years for BD+17° 3248. Once a white dwarf star is formed, it begins to undergo radia-ve cooling and the surface temperature steadily drops. By measuring the temperatures of the coolest of these white dwarfs and comparing them to their expected ini-al temperature, an age es-mate can be made. With this technique, the age of the globular cluster M4 was es-mated as 12.7 ± 0.7 billion years. Globular clusters are among the oldest objects in the Milky Way Galaxy, which thus set a lower limit on the age of the galaxy. Age es-mates of the oldest of these clusters gives a best fit es-mate of 12.6 billion years, and a 95% confidence upper limit of 16 billion years.
In 2007, a star in the galac-c halo, HE 1523-‐0901, was es-mated to be about 13.2 billion years old, ≈0.5 billion years less than the age of the universe. As the oldest known object in the Milky Way at that -me, this measurement placed a lower limit on the age of the Milky Way. This es-mate was determined using the UV-‐Visual Echelle Spectrograph of the Very Large Telescope to measure the rela-ve strengths of spectral lines caused by the presence of thorium and other elements created by the R-‐process. The line strengths yield abundances of different elemental isotopes, from which an es-mate of the age of the star can be derived using nucleocosmochronology.
The age of stars in the galac-c thin disk has also been es-mated using nucleocosmochronology. Measurements of thin disk stars yield an es-mate that the thin disk formed 8.8 ± 1.7 billion years ago. These measurements suggest there was a hiatus of almost 5 billion years between the forma-on of the galac-c halo and the thin disk.
Prof Ben More, Uni Zurich
Formation of the Earth – 4.6 Ga 1017 s
h]p://en.wikipedia.org/wiki/Earth
The earliest material found in the Solar System is dated to 4.5672±0.0006 Ga therefore, it is inferred that the Earth must have been formed by accre-on around this -me. By 4.54±0.04 Ga the primordial Earth had formed. The forma-on and evolu-on of the Solar System bodies occurred in tandem with the Sun. In theory a solar nebula par--ons a volume out of a molecular cloud by gravita-onal collapse, which begins to spin and fla]en into a circumstellar disk, and then the planets grow out of that in tandem with the star. The assembly of the primordial Earth proceeded for 10–20 Ma.
Formation of Today’s Continents – 200 Ma 1016 s
h]p://en.wikipedia.org/wiki/Pangaea
Pangaea was a supercon-nent that existed during the late Paleozoic and early Mesozoic eras, forming approximately 300 million years ago. It began to break apart around 200 million years ago. The single global ocean which surrounded Pangaea is accordingly named Panthalassa.
The name Pangaea is derived from Ancient Greek pan (πᾶν) meaning "en-re", and Gaia (Γαῖα) meaning "Mother Earth". The name was coined during a 1927 symposium discussing Alfred Wegener's theory of con-nental driC. In his book The Origin of Con-nents and Oceans (Die Entstehung der Kon-nente und Ozeane), first published in 1915, he postulated that prior to breaking up and driCing to their present loca-ons, all the con-nents had at one -me formed a single supercon-nent which he called the "Urkon-nent". Originally, this theory was rejected because the predominant theory was that the Earth was cooling and shrinking, with mountains being the last regions to shrink. Wegener's theory that mountains were made by two land masses colliding with each other seemed unlikely because it was thought that nothing could move a landmass as large as a con-nent.
Formation of the Alps – 30 Ma 1015 s
h]p://www.geosci.usyd.edu.au/users/prey/ACSGT/EReports/eR.2003/GroupD/Report1/web%20pages/swiss_alps.html
The Swiss Alps are a mountain range that formed aCer the break-‐up of the supercon-nent Pangea. During the mesozoic, there was an ocean that separated Europe from Africa called the Tethys Ocean. The subduc-on of this basin and the collision of Africa with the Eurasian plate is what caused the forma-on of these mountains. There were two main episodes of orogenisis, one during the Cretaceous causing the forma-on of the eastern and western Alps, the second during the Ter-ary resul-ng in the forma-on of the central Alps. These episodes of deforma-on and orogeny scraped off and thrusted large por-ons of sediments from both the Eurasian and African Plates that are now part of the Alps. These features are called nappes are only a few kilometers thick but s-ll contribute to overall con-nental thickening. The final collision between Africa and Eurasia also upliCed por-ons of oceanic crust called ophiolites into the orogeny. The Alps are a highly complex regime comprising both ophiolites and nappes, as well as high grade metamorphism, faul-ng and folding.
Bernard Lang, Uni Geneva
Vauthey Group
Evolution of Humans – 7 Ma 1014 s
h]p://en.wikipedia.org/wiki/Timeline_of_human_evolu-on
Hominina speciate from the ancestors of the chimpanzees. Both chimpanzees and humans have a larynx that reposi-ons during the first two years of life to a spot between the pharynx and the lungs, indica-ng that the common ancestors have this feature; a precondi-on for vocalized speech in humans. The latest common ancestor lived around the -me of Sahelanthropus tchadensis, ca. 7 Ma; S. tchadensis is some-mes claimed to be the last common ancestor of humans and chimpanzees, but there is no way to establish this with any certainty. The earliest known representa-ve from the ancestral human line post-‐da-ng the separa-on with the chimpanzee lines is Orrorin tugenensis (Millennium Man, Kenya; ca. 6 Ma).
CO2 Cycle from Arctic Ice – 100000 a 1013 s
h]p://en.wikipedia.org/wiki/Carbon_dioxide_in_Earth%27s_atmosphere
The concentra-on of carbon dioxide (CO2) in Earth's atmosphere determines its contribu-on to the greenhouse effect and the rates of plant and algal photosynthesis. The concentra-on has increased markedly in the 21st century, at a rate of 2.0 ppm/yr during 2000–2009 and faster since then. It was 280 ppm in pre-‐industrial -mes, and has risen to 392 ppm (parts per million) in 2013 with the increase largely a]ributed to anthropogenic sources. About 57% of the CO2 emissions go to increase the atmospheric level, with much of the remainder contribu-ng to ocean acidifica-on. Carbon dioxide is used in photosynthesis, and is also a prominent greenhouse gas. Despite its rela-vely small overall concentra-on in the atmosphere, CO2 is an important component of Earth's atmosphere because it absorbs and emits infrared radia-on. The present level appears to be the highest in the past 800,000 years and likely the highest in the past 20 million years, but well below 10% of its 500-‐million-‐year peak.
Growth Time of a 4 m Stalactite – 30000 a 1012 s
h]p://www.environmentalgraffi-.com/news-‐biggest-‐stalac-tes-‐and-‐stalagmites-‐earth
Stalac-tes hanging from the ceilings of caverns commonly exhibit a central tube or the trace of a former tube whose diameter is that of a drop of water hanging by surface tension. A drop on the -p of a growing stalac-te leaves a deposit only around its rim. Downward growth of the rim makes the tube. The simplest stalac-te form, therefore, is a thin-‐walled stone straw, and these fragile forms may reach lengths of 0.5 m (20 inches) or more where air currents have not seriously disturbed the growth. The more common form is a downward-‐tapering cone and is simply a thickening of the straw type by mineral deposi-on from a film of water descending the exterior of the pendant.
Development of Western Science – 3000 a 1011 s
h]p://www.flowo}istory.com/readings-‐flowcharts/revival-‐west/the-‐age-‐enlightenment/fc97
Western science, like so many other aspects of Western Civiliza-on, was born with the ancient Greeks. They were the first to explain the world in terms of natural laws rather than myths about gods and heroes. They also passed on the idea of the value of math and experiment in science, although they usually thought only in terms of one to the exclusion of the other. It is easy for us to be cri-cal of their early scien-fic theories, but we must remember several things about their world. First, by that -me, the human race had learned to exploit the environment for survival (e.g., agriculture, woven cloth, metallurgy, etc.), but knew li]le about the physical laws that rule nature and the universe. Also, there were no telescopes, microscopes, or other instruments to aid the naked eye in its observa-ons and measurements. Everything they learned about the natural world had to be done with the unaided senses and whatever ra-onal deduc-ons they could make based on them.
Development of Calculus – 350 a 1010 s
h]p://www.uiowa.edu/~c22m025c/history.html
The discovery of calculus is oCen a]ributed to two men, Isaac Newton and Go�ried Leibniz, who independently developed its founda-ons. Although they both were instrumental in its crea-on, they thought of the fundamental concepts in very different ways. While Newton considered variables changing with -me, Leibniz thought of the variables x and y as ranging over sequences of infinitely close values. He introduced dx and dy as differences between successive values of these sequences. Leibniz knew that dy/dx gives the tangent but he did not use it as a defining property. On the other hand, Newton used quan--es x' and y', which were finite veloci-es, to compute the tangent. Of course neither Leibniz nor Newton thought in terms of func-ons, but both always thought in terms of graphs. For Newton the calculus was geometrical while Leibniz took it towards analysis.
Development of Personal Computers – 25 a 109 s
h]p://www.computerhistory.org/
Evolu-on of Apple computers over a period of 25 years
Duration of a Bachelor or PhD Program – 3 a 108 s
h]p://www.phdcomics.com
3 to 4 year program depending on university
Annual Cycle – 12 months 107 s
h]p://en.wikipedia.org/wiki/Year
A year is the orbital period of the Earth moving around the Sun. For an observer on the Earth, this corresponds to the period it takes the Sun to complete one course throughout the zodiac along the eclip-c.
In astronomy, the Julian year is a unit of -me, defined as 365.25 days of 86400 SI seconds each.
Due to the Earth's axial -lt, the course of a year sees the passing of the seasons, marked by changes in weather, hours of daylight, and consequently vegeta-on and fer-lity. In temperate and subpolar regions, generally four seasons are recognized: spring, summer, autumn and winter, astronomically marked by the Sun reaching the points of equinox and sols-ce, although the clima-c seasons lag behind their astronomical markers. In some tropical and subtropical regions it is more common to speak of the rainy (or wet, or monsoon) season versus the dry season.
A calendar year in the Gregorian calendar (as well as in the Julian calendar) has either 365 or 366 days.
Lunar Cycle – 29.5 days 106 s
h]p://stardate.org/nightsky/moon
The Moon has phases because it orbits Earth, which causes the por-on we see illuminated to change. The Moon takes 27.3 days to orbit Earth, but the lunar phase cycle (from new Moon to new Moon) is 29.5 days. The Moon spends the extra 2.2 days "catching up" because Earth travels about 45 million miles around the Sun during the -me the Moon completes one orbit around Earth.
At the new Moon phase, the Moon is so close to the Sun in the sky that none of the side facing Earth is illuminated. In other words, the Moon is between Earth and Sun. At first quarter, the half-‐lit Moon is highest in the sky at sunset, then sets about six hours later. At full Moon, the Moon is behind Earth in space with respect to the Sun. As the Sun sets, the Moon rises with the side that faces Earth fully exposed to sunlight.
The Eukaryotic Cell Cycle – 1 day 105 s
h]p://www.ncbi.nlm.nih.gov/books/NBK9876/
The division cycle of most cells consists of four coordinated processes: cell growth, DNA replica-on, distribu-on of the duplicated chromosomes to daughter cells, and cell division. In bacteria, cell growth and DNA replica-on take place throughout most of the cell cycle, and duplicated chromosomes are distributed to daughter cells in associa-on with the plasma membrane. In eukaryotes, however, the cell cycle is more complex and consists of four discrete phases. Although cell growth is usually a con-nuous process, DNA is synthesized during only one phase of the cell cycle, and the replicated chromosomes are then distributed to daughter nuclei by a complex series of events preceding cell division. Progression between these stages of the cell cycle is controlled by a conserved regulatory apparatus, which not only coordinates the different events of the cell cycle but also links the cell cycle with extracellular signals that control cell prolifera-on.
Sleep Cycle – 8 h 104 s
h]p://psychology.about.com/od/statesofconsciousness/a/SleepStages.htm
The Beginnings of Sleep: During the earliest phases of sleep, you are s-ll rela-vely awake and alert. The brain produces what are known as beta waves, which are small and fast. As the brain begins to relax and slow down, slower waves known as alpha waves are produced. During this -me when you are not quite asleep, you may experience strange and extremely vivid sensa-ons known as hypnagogic hallucina-ons. Common examples of this phenomenon include feeling like you are falling or hearing someone call your name. Another very common event during this period is known as a myoclonic jerk. If you've ever startled suddenly for seemingly no reason at all, then you have experienced this odd phenomenon.
Stage 1: Is the beginning of the sleep cycle, and is a rela-vely light stage of sleep. Stage 1 can be considered a transi-on period between wakefulness and sleep. In Stage 1, the brain produces high amplitude theta waves, which are very slow brain waves. This period of sleep lasts only a brief -me (5-‐10 min.). If you awaken someone during this stage, they might report that they weren't really asleep.
Stage 2: Is the second stage of sleep and lasts for approximately 20 min. The brain begins to produce bursts of rapid, rhythmic brain wave ac-vity known as sleep spindles. Body temperature starts to decrease and heart rate begins to slow.
Stage 3: Deep, slow brain waves known as delta waves begin to emerge during stage 3 sleep. Stage 3 is a transi-onal period between light sleep and a very deep sleep.
Stage 4: Is some-mes referred to as delta sleep because of the slow brain waves known as delta waves that occur during this -me. Stage 4 is a deep sleep that lasts for approximately 30 minutes.
Stage 5: Most dreaming occurs during the fiCh stage of sleep, known as rapid eye movement (REM) sleep. REM sleep is characterized by eye movement, increased respira-on rate and increased brain ac-vity. Dreaming occurs due because of increased brain ac-vity, but voluntary muscles become paralyzed.
The Sequence of Sleep Stages: It is important to realize, however, that sleep does not progress through these stages in sequence. Sleep begins in stage 1 and progresses into stages 2, 3 and 4. ACer stage 4 sleep, stage 3 and then stage 2 sleep are repeated before entering REM sleep. Once REM sleep is over, the body usually returns to stage 2 sleep. Sleep cycles through these stages approximately four or five -mes throughout the night. On average, we enter the REM stage approximately 90 minutes aCer falling asleep. The first cycle of REM sleep might last only a short amount of -me, but each cycle becomes longer. REM sleep can last up to an hour as sleep progresses.
Visual (Rhodopsin) Cycle – 30 min 103 s
h]p://www.vetmed.vt.edu/educa-on/curriculum/vm8054/eye/rhodopsn.htm
h]p://www.reference.com/browse/rhodopsin
The visual pigment rhodopsin (some-mes called "visual purple") is bound to the plasma membrane of the rod and forms transmembrane protein complexes within it. Rhodopsin undergoes a cyclic decomposi-on and recons-tu-on in response to the presence of light. This rather complicated cycle is the basis for absorp-on of light and its transduc-on into a nervous signal.
The visual cycle is a circular enzyma-c pathway, which is the front-‐end of phototransduc-on. It regenerates 11-‐cis-‐re-nal. For example, the visual cycle of mammalian rod cells is as follows:
1. all-‐trans-‐re-nyl ester + H2O → 11-‐cis-‐re-nol + fa]y acid; RPE65 isomerohydrolases,
2. 11-‐cis-‐re-nol + NAD+ → 11-‐cis-‐re-nal + NADH + H+; 11-‐cis-‐re-nol dehydrogenases,
3. 11-‐cis-‐re-nol + aporhodopsin → rhodopsin + H2O; forms Schiff base linkage to lysine, -‐CH=N+H-‐,
4. rhodopsin + hν → metarhodopsin II; 11-‐cis photoisomerizes to all-‐trans, rhodopsin + hν → photorhodopsin → bathorhodopsin → lumirhodopsin → metarhodopsin I → metarhodopsin II,
5. metarhodopsin II + H2O → aporhodopsin + all-‐trans-‐re-nal,
6. all-‐trans-‐re-nal + NADPH + H+ → all-‐trans-‐re-nol + NADP+; all-‐trans-‐re-nol dehydrogenases,
7. all-‐trans-‐re-nol + fa]y acid → all-‐trans-‐re-nyl ester + H2O; lecithin re-nol acyltransferases (LRATs).
Steps 3,4,5,6 occur in rod cell outer segments; Steps 1, 2, and 7 occur in re-nal pigment epithelium (RPE) cells.
Type 2 rhodopsin (rainbow colored) embedded in a lipid bilayer (heads red and tails blue) with transducin below it. Gtα is colored red, Gtβ blue, and Gtγ yellow. There is a bound GDP molecule in the Gtα-‐subunit and a bound re-nal (black) in the rhodopsin. The N-‐terminus terminus of rhodopsin is red and the C-‐terminus blue. Anchoring of transducin to the membrane has been drawn in black.
Frying an Egg – 2 min 102 s
h]p://voices.yahoo.com/the-‐kitchen-‐chemist-‐happens-‐fry-‐egg-‐2969005.html
The front-‐right burner is on in your gas stove, and you have a small stainless steel skillet with a few tablespoons of bu]er melted in it. You grab hold of a jumbo white egg, and cracking it on the edge of the skillet, you spread the shell halves apart and deposit the contents of the egg without breaking the yolk, right into the center of the sizzling bu]er. You toss the shells, repeat this process once or twice more, and then you wash your hands and dry them. Within seconds of the -me the clear albumen strikes the hot bu]er, it begins turning white. To speed up the process, you take a spoon and dip up some of the molten bu]er, splashing it onto the white and the yolk, un-l it is at least partly cooked, with the film over the yolk clouding up. Even if you don't want the yolk cooked solid, you probably like the white totally cooked. When you are done, the clear albumen is completely white. Why? Why does an egg white turn white? What is the chemistry of it?
Protein DenaturaIon
This process that you have observed so many dozens of -mes is called denatura6on. The albumen or "white" of an egg is a solu-on of proteins in water surrounding the yolk of an egg. Proteins are chains of various amino acids. When heat is applied to the white of an egg, the protein chains are broken, and they then recombine in a different order. This s-ffens and whitens the albumen of an egg. Also some of the moisture is driven off. The whole process is termed denatura-on. The average person prefers to think of it as "cooking."
PepIde Linkage
Proteins are important chemicals found throughout nature, that possess a "pep-de" linkage. A pep-de linkage consists of a carboxylic group, symbolized by -‐COOH, combined with an amino group, symbolized by -‐NH2, minus water. Thus, if you have two molecules, say,
R1-‐COOH and R2-‐NH2, and you combine them you get, at first,
R1-‐COO-‐-‐NH4+-‐R2 (this is an amine salt, which, aCer removing a water, becomes,)
R1-‐CONH2-‐R2
The -‐CONH2-‐ por-on of the molecule is called a pep-de linkage.
World Record 100 m – 9.58 s 101 s
h]p://www.sciencekids.co.nz/sciencefacts/topten/fastestmanintheworld.html
Who is the fastest man in the world? Currently the answer is Jamaican sprinter Usain Bolt, he’s also the fastest man in history with a world record -me of 9.58 seconds. The fastest woman is history is Florence Griffith-‐Joyner with a world record -me of 10.49. Take a look at the other fastest people ever, what countries are they from? Are humans ge�ng faster?
Blink of an Eye – 1 s 100 s
h]p://www.madsci.org/posts/archives/1998-‐11/911697403.Me.r.html
The average -me it takes for a complete human blink is about 300 to 400 milliseconds or 3/10ths to 4/10ths of a second. Of course this is an average only and can differ from person to person. Also, there are other factors that can affect blink speed, like fa-gue, medica-ons, diseases, and injury to the eye area. Most factors decrease or slow the blink rate.
Andrin Caviezel, ETH Zurich
Beaud Group
The Speed of Thoughts – 300 ms 10-‐1 s
Current Biology 1994, Vol 4 No 12, 1125
The 'speed of thought' may be measured in a number of ways by researchers working in different disciplines, such as cogni-ve psychologists or neuropsychologists. Only the neurophysiologist, however, is able to go to the heart of the ma]er -‐ the speed of the response of neurons. Such inves-ga-ons provide crucial informa-on for all those working on how the brain works, as it allows them to base their ideas in a biologically plausible framework. In almost all studies of a neuron's response to a s-mulus, the response is sampled over long -me periods, usually around 300 to 500 milliseconds (ms). Is this a biologically plausible length of -me? We know that it is possible to recognize and respond to a visual s-mulus within 400-‐500 ms. If one considers that at least half of this -me is involved in the genera-on and implementa-on of motor commands, then the total amount of -me available for processing in the whole visual system is considerably less than the period over which a neuron's response is conven-onally measured. A number of recent results allow es-ma-on of the length of -me each neuron must be ac-ve to mediate visual percep-on; the processing -me inferred from these results may have implica-ons for how neuronal responses are measured and how these responses are interpreted.
Enzyme Triggered Reactions – 10 ms 10-‐2 s
h]p://www.eurekalert.org/pub_releases/2003-‐05/uonc-‐wec050503.php
Without enzyme catalyst, slowest known biological reac-on takes 1 trillion years
All biological reac-ons within human cells depend on enzymes. Their power as catalysts enables biological reac-ons to occur usually in milliseconds. But how slowly would these reac-ons proceed spontaneously, in the absence of enzymes -‐ minutes, hours, days? And why even pose the ques-on? One scien-st who studies these issues is Dr. Richard Wolfenden, Alumni dis-nguished professor of biochemistry and biophysics and chemistry at the University of North Carolina at Chapel Hill and a member of the Na-onal Academy of Sciences. In 1998, he reported a biological transforma-on deemed "absolutely essen-al" in crea-ng the building blocks of DNA and RNA would take 78 million years in water.
Protein Folding – us … h, mostly ms 10-‐3 s
h]p://en.wikipedia.org/wiki/Protein_folding
Protein folding is the process by which a protein structure assumes its func-onal shape or conforma-on. It is the physical process by which a polypep-de folds into its characteris-c and func-onal three-‐dimensional structure from random coil. Each protein exists as an unfolded polypep-de or random coil when translated from a sequence of mRNA to a linear chain of amino acids. This polypep-de lacks any stable (long-‐las-ng) three-‐dimensional structure. Amino acids interact with each other to produce a well-‐defined three-‐dimensional structure, the folded protein, known as the na-ve state. The resul-ng three-‐dimensional structure is determined by the amino acid sequence.
The correct three-‐dimensional structure is essen-al to func-on, although some parts of func-onal proteins may remain unfolded. Failure to fold into na-ve structure generally produces inac-ve proteins, but in some instances misfolded proteins have modified or toxic func-onality. Several neurodegenera-ve and other diseases are believed to result from the accumula-on of amyloid fibrils formed by misfolded proteins. Many allergies are caused by incorrect folding of some proteins, for the immune system does not produce an-bodies for certain protein structures.
Levinthal's paradox is a thought experiment, also cons-tu-ng a self-‐reference in the theory of protein folding. In 1969, Cyrus Levinthal noted that, because of the very large number of degrees of freedom in an unfolded polypep-de chain, the molecule has an astronomical number of possible conforma-ons. An es-mate of 3300 or 10143 was made in one of his papers. The Levinthal paradox observes that if a protein were folded by sequen-ally sampling of all possible conforma-ons, it would take an astronomical amount of -me to do so, even if the conforma-ons were sampled at a rapid rate (on the nanosecond or picosecond scale). Based upon the observa-on that proteins fold much faster than this, Levinthal then proposed that a random conforma-onal search does not occur, and the protein must, therefore, fold through a series of meta-‐stable intermediate states.
Lightening Propagation– 100 us 10-‐4 s
Phys. Rev. Le]. 108, 138104 (2012)
One way that animals, including humans, locate a sound source is by detec-ng slight differences in the arrival -mes of sound waves to the leC and right ears. Animal auditory systems are capable of detec-ng interaural -me differences of less than 100 microseconds, even though individual neurons respond on the rela-vely sluggish -me scale of milliseconds.
Prof Jean-‐Pierre Wolf, Uni Geneva
Highest Audible Frequency – 50 us 10-‐5 s
h]p://hyperphysics.phy-‐astr.gsu.edu/hbase/sound/earsens.html
The highest frequency audible to the human ear is 20 kHz, and only takes 50 microseconds.
A Ligand in a Protein 10-‐6 s The movie shows the unbinding of an arylsulfonamide ligand from a pocket inside the carbonic anhydrase II (hCa II) protein—responsible for the reversible hydra-on of carbon dioxide. Overexpression of CA has been associated with different human diseases, such as osteoporosis and glaucoma. A number of clinically-‐used drugs are known to display CA-‐inhibitory proper-es.
Markus Meuwly, Uni Basel
Light Traveling a Distance of 100 m – 300 ns 10-‐7 s
h]p://en.wikipedia.org/wiki/Speed_of_light
Compare to 100m world record men.
Fluorescence Lifetime – 0.5 … 20 ns 10-‐8 s
h]p://chemwiki.ucdavis.edu/Physical_Chemistry/Spectroscopy/Electronic_Spectroscopy/Fluorescence
Fluorescence, a type of luminescence, occurs in gas, liquid or solid chemical systems. Fluorescence is brought about by absorp-on of photons in the singlet ground state promoted to a singlet excited state. The spin of the electron is s-ll paired with the ground state electron, unlike phosphorescence. As the excited molecule returns to ground state, it involves the emission of a photon of lower energy, which corresponds to a longer wavelength, than the absorbed photon.
Ursula Röthlisberger, EPFL
Transistor Switching Time – 3 ns 10-‐9 s
h]p://www.intel.com/pressroom/kits/45nm/Intel45nmFunFacts_FINAL.pdf
A 45nm transistor can switch on and off approximately 300 billion -mes a second. A beam of light travels less than a tenth of an inch during the -me it takes a 45nm transistor to switch on and off.
Photodissociation of Molecules – 100 ps 10-‐10 s
h]p://www.chemphys.lu.se/old/kfresearch/rdynamics.html
In a simplified picture we can visualize the photodissocia-on as follows: A short femtosecond laser pulse promotes the transi-on to a repulsive poten-al surface and the molecule will dissociate. In the gas phase, the story more or less ends here. It is not likely that the dissocia-ng fragments ever will encounter each other again. But adding solvent molecules around the run away fragments the story con-nues. Now, it is possible for the fragments to recombine into the original configura-on i.e. geminate recombina-on. The surrounding solvent molecules act as a cage, and provide the -me and space for the fragments to find the way back to each other. And also, as we have shown for several halo alkanes, they can recombine into another configura-on by in-‐cage isomerisa-on. Of course, there is s-ll the possible route to finite dissocia-on as in the gas phase and the final products will be the dissocia-ng fragments. The solvent is not only a sta-c cage that keeps the molecule together, but interacts in many ways with the fragments on the course of events. One example is that the surrounding solvent will act as a heat reservoir for energy dissipa-on since the excita-on to the repulsive state provides an excess of energy. To what extent various process will occur is a delicate interplay between solute-‐solvent interac-ons, solvent dynamics and the poten-al energy surfaces of the reac-on.
The movie shows the photodissocia-on of a sulfuric acid molecule. It illustrates the two concepts of kine-cs and dynamics: aCer excita-on by a light quantum the molecule shakes and ra]les (“is vibra-onally excited”) for about 100 picoseconds before a hydrogen atom from one OH group switches bonds and a water molecule detaches within tens of femtoseconds. Kine-cs is governed by the probability for the last step to occur, while dynamics describes the mo-on of the actual detachment process and is thus much faster. (<<< men-on rela-on to acid rain ? >>>)
Markus Meuwly, EPFL
Molecular Rotation – 3…300 ps 10-‐11 s
h]p://mackenzie.chem.ox.ac.uk/teaching/Molecular%20Rota-onal%20Spectroscopy.pdf
The free rota-on of a rigid object with no forces ac-ng on it is of obvious importance in chemistry. It is also a very complicated problem. In simple examples the angular velocity is simple to interpret and remains constant throughout the rota-on. This is true of a rigid object rota-ng about one of its principal axes, however objects rota-ng about an axis that is not a principal axis wobble during the course of the rota-on (think about the mo-on of a rugby ball in flight). The result of this is that the angular velocity is not constant and the orienta-on of the moment of iner-a is not constant either.
However, the conserva-on laws ensure that two quan--es are constant: the angular momentum, which is given in terms of the iner-al tensor as
Markus Meuwly, Uni Basel
Breaking and Forming of Hydrogen Bonds – 1 ps 10-‐12 s
h]p://www1.lsbu.ac.uk/water/hbond.html
Polar covalent bonds are responsible for the charged regions in a water molecule. Water molecules in close proximity are a]racted to the oppositely charged regions of adjacent molecules to form hydrogen bonds. Every water molecule can form hydrogen bonds with mul-ple partners and these associa-ons change frequently.
Peter Hamm, Uni Zurich
Cis/Trans Isomerization of Retinal – 200 fs 10-‐13 s
h]p://www.elmhurst.edu/~chm/vchembook/534photochemical.html
Photochemical events in vision involve the protein opsin and the cis/trans isomers of re-nal.
Opsin does not absorb visible light, but when it is bonded with 11-‐cis-‐re-nal to form rhodopsin, which has a very broad absorp-on band in the visible region of the spectrum. The peak of the absorp-on is around 500 nm, which matches the output of the sun closely.
Upon absorp-on of a photon of light in the visible range, cis-‐re-nal can isomerize to all-‐trans-‐re-nal. The shape of the molecule changes as a result of this isomeriza-on. The molecule changes from an overall bent structure to one that is more or less linear. All of this is the result of trigonal planar bonding (120 o bond angles) about the double bonds.
Ursula Röthlisberger, EPFL
Molecular Vibration – 8 fs … 1 ps 10-‐14 s
h]p://en.wikipedia.org/wiki/Molecular_vibra-on
h]p://www.fuw.edu.pl/~krp/papers/vib_spli�ng_prl.pdf
A molecular vibra-on occurs when atoms in a molecule are in periodic mo-on while the molecule as a whole has constant transla-onal and rota-onal mo-on. The frequency of the periodic mo-on is known as a vibra-on frequency, and the typical frequencies of molecular vibra-ons range from less than 1012 to approximately 1014 Hz.
Fundamental vibra-on of H2: 4161 cm-‐1 -‐> T = 8.02 fs
Oscillation Period of Visible Light – 1.3 … 2.5 fs 10-‐15 s
h]p://www.mc2.chalmers.se/pl/lc/engelska/tutorial/light.html
Visible light: 400 nm … 750 nm -‐> 1.33 fs … 2.50 fs
Electron Dynamics – 100 as 10-‐16 s
h]p://newscenter.lbl.gov/news-‐releases/2010/08/04/electrons-‐moving/
h]p://www.rsc.org/chemistryworld/News/2010/June/09061002.asp
Exploi-ng the a]osecond light source technology to inves-gate extremely rapid electron dynamics in atomic and molecular systems. The electronic mo-on in atoms and molecules occurs on a very fast -mescale: the Bohr orbit of the ground state electron in the hydrogen atom corresponds to 150 a]oseconds.