Overcome space and time. Alike based internet. And the effects of city lights on nature. But lets start at the beginning with how we see light. When light enters our eye it hits the retina. And is received by photo receptor cells the socalled rod cells respond to light and dark the cones are responsible for color vision but we only see the light that actually enters our eyes if you are in zambia wanted to know more. How those light travel. During a thunderstorm or you see the light. Things straight away but we hear the thunder with a delay. Thats because sound waves move slowly or as light travels super fast at 300000 kilometers per 2nd. It maintains that speed in space where theres a vacuum and it moves only slightly slower through the earths atmosphere but other media slow it down for example water in which it travels at a mere 225000 kilometers a 2nd. Life travels like ripples spreading on the surface of a liquid in all directions simultaneously. And in Straight Lines which is why we talk of light rays sometimes its even possible for us to see the. Light that does not strike our retinas remains invisible we only see light inside view for example when it scattered off particles of dust or droplets of water and into our hives. On a rough surface light rays scatter in all directions in Shallow Water this produces wavy abstract patterns. When this light hits a smooth as glass surface it changes direction through refraction and is separated into different colors. Like continues to move until it meets an obstacle in the case of dark clouds it simply swallowed up. And thanks to help are dying star in special theory of relativity we know that nothing can travel at or beyond the speed of light. What is light exactly for one thing its electromagnetic radiation thus only a small section of it is visible to us between violets and red over wavelengths between 300. 00. And 715 enemy. Objects illuminated by that light of a simple to us we dont actually see the objects themselves but the radiation that they reflect theres much more to life than meets the eye. It brightens things up everywhere light is omnipresent but what kind of weird matter is light isnt even matter at all or is it pure energy light only seems familiar to us might particle or photons open the doors to a truly strange world scientists used to believe that light comprised tiny bulbs zipping around through space then light was regarded as a wave but today we know that depending on the experiment light can be either one or the other. Like the wave light is a particle it depends on how we observe it in a sense its both both at the same time and thats truly bizarre. Might may indeed seem like a far fetched notion but it exists we literally see it constantly but if you take a closer look at it it practically vanishes not least if you try to wave a photon. Yes this really is kind of strange at 1st glance that it. Was. Also. So im now sitting on this chair and i have a certain mass if i had some scales it would be my rest mass. That also applies to the elementary particles that were made up of. But by the photon its different it actually has no rest mass at all. So a photon both exists and does not exist at the same time photons are never at rest according to physicists theyre constantly in motion whats more at the speed of light which is where the next strange phenomenon lies at 1st glance the speed of light seems the world and we fast. 1. 3 seconds to the moon or one second to circle the earth 7 times. But looking further afield theres no longer sound so awesome. Then light needs an hour and a half to go all the way to saturn the farthest planet that can be seen with the naked eye and getting to the nearest star takes 4 years. And to the andromeda galaxy and out of this world 4 and a half 1000000 years. 300000 kilometers per 2nd thats not just any speed nothing moves faster absolutely nothing and never the light from a cars headlamps will not move any faster if the car is also moving it doesnt need to. Be very light always moves at the speed of light i cant add to it but the consequence of this if you think about it for half an hour is that time does not always pass at the same speed the currents does need side and he mug life never get. Thanks to Albert Einstein who needed a bit more than half an hour we now know that space and time become distorted when we move the faster we go the stronger the distortion and at 300000 kilometers per 2nd photons move very fast the distortion is so extreme at this speed that from the photons perspective time stands still and space starts expanding to go any faster when the point lets. The photons perspective. The universe. No longer expounds im everywhere in the universe at the same time unfortunately we cant put ourselves in the photons perspective that would be fantastic if we could join it and also have that perspective everybody that has a mass needs infinite amounts of energy to reach the speed of light the food and all of anything from the consequences for totally out of us to a photon would be very exotic it would have no space and no time in climate science. Its no wonder that light inspires contemplation. My approach to light as such is down to earth enough but the fact that light remains a secret on a level thats not the mystical nor romantic. Notion is well that is a factor for me. During a quiet all month when im relaxed. Of course i think about how what i do every day can be incorporated into fundamental equations the fundamental laws of nature to call in playing the light shone because the thing is said so that i thought. You might know folks some of the most profound mysteries in our world not just at the altar as the various religions but also in the illuminating minds of physicists. Pretty strange stuff lives photons have actually been used to teleport information thanks to a phenomenon called Quantum Entanglement 2 particles such as photons can be correlated in such a way that they always do as the other does no matter how far away they are from each other. Like faraway clocks that somehow synchronize. Einstein 1st described this effect as spooky action at a distance the entangled photons can Exchange Data almost instantaneously but in fact its possible to transmit data at high speeds with normal life sources using a life of intellect. When the lights go on here not only does the room brighten but data is being transmitted these researchers at the found the hit Earth Institute in berlin are working on wireless data communication using lights its a technology known as life i short for light for delicacy the visible light transmitters are l. E. D. Lamps this is. Early days are the main light source for this technology other Light Sources would be far too slow to be useful. The l e ts are switched on and all fixed really rapidly sensors on the receiver device capture the signal the speed of the signal transmission is very high thanks to the fact that life i usually life is a very Broad Spectrum of wireless data from our ceiling lights its super fast but could it be a problem for our vision. The question is does it the whole time. We can see down here the modulation is very very high far higher than the eye can detect. The small green lamps flickering here are just playful Design Elements the device was newly developed by the berlin scientists and the green lights tell the user that its operating the prerequisite for this optical wireless system to function is that there must be visual contact between transmitter and receiver if the light source is interrupted the signal is lost the Data Transmission rate drops to 0. An advantage of this optical data connection is that it can be easily confined to a room all i need to do is close the blinds and im completely isolated from the outside world. And all my data stay in the room when theyre being transmitted. That is a definitive advantage compared to a radio which you can easily be picked up from the outside. The system doesnt allow the Data Transmission to be disrupted from might side the life internet was tested in a Pilot Project in collaboration with the car maker the technology is packed into this box. And other life i devices were set up at fixed points in such a way that there was always at least one visual contact despite the constant motion of the robots the Data Transmission remained stable a big success for the project. I was run as if the in my view this technology will 1st be applied in an industrial field. Thats for an objective need to exist we have to show that we can fulfill certain specifications with this technology and at the same time that we have a professional area where it can and will find an application. After that Data Transmission by life could move into daily life such as in museums or in public transport situations where there are many users at once or where why fight transmission is faulty but 1st a number of problems have to be solved. It means is. That if you move around in a room or you go from that room to another you have to have a system there that can guarantee an interrupt a Data Transmission but. We already have those kinds of solutions in the radio frequency area we have to adapt those solutions to optics. Only then will we have a fully functioning system in this system where the researchers hope to master those problems within 3 years bringing life i out of its nice position and into the life. Theres nothing like twinkling lights to get you into the festive spirit. But human made lighting it nice is bad for the environment Light Pollution is a growing problem across the planet some of the artificial light that shines into the atmosphere is reflected back creating a dome of diffuse like known as sky glow it can have devastating consequences for creatures who survival depends on the darkness. In germany there are many places where it gets truly dark at night one of them is lake stateliness brandenburg ideal can. Visions for a unique experiment its 3 oclock in the morning this is when water police tend to come to the surface of the lake to feed an alkie biologist is waiting for them. The light from their head torches would disturb the experiment so they switch them off only infrared light is allowed. Ok and his team are exploring the effects of sky glow on water. Theyve positioned l. E. D. Lights in circles in a number of test basins they simulate various degrees of Light Pollution. And. This is explained its extremely hard to develop a test model which allows you to observe the effects of sky glow on an ecosystem. We have here is a very very diffuse light but it still affects vast swathes of the landscape at night huge areas across Germany Europe all over the world are affected by sky glow the. Sky glow and effect on the top. 24 test basins make up a Floating Laboratory the researchers will be trying to identify the extent that sky glow affects the underwater world the life processes of marine organisms are determined by the intensity of light the researchers take water samples from the test cylinders illuminated to varying degrees samples are taken from various depths and at different times of night and day every type of marine organism from bacteria to algae to fish is of interest to the fish as the light allows the fish to see better as they feed and so all plankton. The water fleas that were researching normally come to the surface at night to feed because they know the fish cant see anything. The they think theyre safe to feed on our. Part they used to like to adjust their depth. In the daytime they head to the bottom of the lake to avoid the fish so light sends them a message that its the twilight sort of permanent twilight and they need to stay in the depths. Were looking at with our water samples as whether theyre consequently feeding on less out in bacteria and whether this development is perhaps triggering other processes. Time for the researches to get some sleep. But they said theyre alarmists for 3 hours later. Just before daybreak theyre up and heading off to fetch more samples from the lake. Their name is to document the marine organisms daily cycles in the past night its way today the illuminated basins are clearly visible against the non illuminated control basin the research is eager to find out of the algae in the basins exposed to sky glow have significantly multiplied because the water fleas stayed away from the surface of the water. Ponds hogan and his team then set about examining their water samples in the lab. They use a piece of equipment that saves them hours of laborious work with a microscope its called a flow cam it automatically scans the sample revealing star shaped rock algae and blue green algae. Everything is counted measured and documented. These are the algae types that water fleas and coppa pods feed on if they dare venture to the lake surface. But the more light there is the less brave they feel. Is sky glow is still a relatively unknown quantity yes our 1st observations indicate that there is something going on even as a result of it. The slightly changing light conditions so we have to assume it affects large areas are. The signs are that Light Pollution adversely affects the food chain and lakes and therefore contributes to more frequent algal bloom fans hope to swedish colleague nice to go are about to do their last water analysis of the day. Not in the lab this time but in the actual time theyre going to install an underwater microscope camera. Once its underwater the device takes a nonstop series of photographs these allow the researches to establish the depth of the organisms and where theyre headed the camera can discern what to fleas as tiny as 1200th of a millimeter. We can see the exact location and movement of these marine organisms they immediately react to changes in light Bright Sunlight makes them head down to the bottom of the lake to. Return to the surface when its dark the findings are clear. Bodies of water and their inhabitants are evidently adversely affected by Light Pollution. If theyre working up of the Data Confirms their hypotheses. And his colleagues will have identified a worldwide problem now the experiment is over the water flees and takes the heat can go back to business as usual today with the sun goes down well have that peace and quiet again. Against behind the scenes television is all about light without it our cameras would record this. The images you see other result of captured light. To get a good shot you need to make sure your settings are right if your camera is out of focus theres no cell. Which in the image. But a new way of capturing light to change that. Whats happening here could revolutionize film and t. V. Production researchers from the Computer Science department of germanys Island University the testing out a brand new way of capturing video using light field cameras they not only measure the intensity of the light emanating from a scene but also the direction in which the individual rays are traveling this is the light field. You closer to for the a few additional photography reproduces a point in a scene on to a point on the film or the sensor. In a light field photography you tray of light is mapped to the point thats being reflected from. So for every point in a scene various rays are reflected in Different Directions which are captured and analyzed and the physics behind it is nothing new but right now the system is only used to stills its allows you to adjust the focus of any point on the image after its been taken if this works for moving images to make a completely change film making. Its was whitefield video cameras would allow you to do all kinds of things and post your pictures at the depth of field angle and Camera Position retrospectively could come off you could even add tracking shots things youd normally need on the original material but what else you could do them afterward you know. This is tim uses 64 individual cameras and therefore send 64 times as much image data 17 gigabytes per 2nd need to be stored in real time not only can you count the position of every point of light you can also count kill light the direction of the light rays. Its already works in the lab. Now they want to test it on to more real Life Conditions at the Animation Institute and not fix bugs theyre planning to film a cellist playing in a studio and capture her movements using light field equipment. And deputed zoom by using light field cameras we hope that well be able to shift the focus around the space in a way thats not possible with real physical lenses damaged nuclear that us is so it is an ocean this is a great example of whats so new and innovative about this technology and the guns and taken no. Preparations are underway for the 1st flight field video shoot in europe they need to break up the cameras and connect fast lengths of cables and prepare the stage for. Star. The scientists and animation specialists will test whether its possible to capture this new form of video and transfer the enormous amounts of data at the same time. Refuses to come out using 64 cameras it gives us 64 different perspectives. In addition to the color and Light Properties of each point you can also calculate the distance this has huge advantages for post production you can add extra facts after the fact who talk and. The like field video shoot has proved to success the team has managed to create a 3 d. Model of the cellist the recordings have captured the amount of light reflecting in all Different Directions from every point in the scene. And this means they can calculate the exact position of each of those points. Theyve also managed to successfully capture her movements using the spatial data they can replicate the challenge from different angles and even have her play polyphonic length. And they are physically abused for eventually in Light Field Technology might work like a kind of scanner system you wouldnt have actual cameras anymore so all the camera work would take place and post. That. Were trying to bring this technology into Film Production for the 1st time and thats whats so special what it does is but it wont be possible until we have the necessary equipment to handle data on the scale of these kinds of productions because people do so in the hope that. The Research Shows demonstrates how the focus can be shifted around the scene. It starts close upon the bow and gradually moves across the various figures. Light field video really does work and in the future it could be possible to capture all of these perspectives and achieve these postproduction effects with just one single camera. If i dont want to read right up it but im going to be ok to. Do you have a science question that youve always wanted answered were happy to help out send it to us as a video text ovoid smell if we answer it on the show well send you a little surprise as a thank you can all just ask. To find out i did over you dot com slash science or drop us a line at g. W. Under school site tech on facebook d w dot science. And that wraps up todays show next time we take a look at hyperloop a technique that picture us poor people and goods at over 1000 kilometers an hour is this the future of transport join us next time to find out by. Shock and awe halflings this is the new ball speaking welcome to the show with the ding dong xoai high end concerts with filibuster his guests. Rocking ses. And then incredible location. Tonight groups. On t. W. Was the speech of his life perhaps his best certainly his most difficult chancellor and would call it addresses the people of east germany shortly after the fall of the wall. The crowd clamors for term unity journalist peter lind was was at the scene. 30 years later looks back on the. President. Starts december 19th. W. D some are good guys keys to safer food. Police to prevent coming. Draw and cook foods to avoid cross comes out. 3rd to kill microorganisms. Keep food it safe temperatures. To prevent bacteria. Out. Use safe water and sea Raw Materials to avoid conflict. Food producers are the ones primarily responsible for the safety of the food. But you can protect yourself and your family from diseases and a whole pipeline the 5 keys to sea for food use them you also have a role to play. This is dean of the news line from thailand revealing the truth about regime death squads in the former soviet republic of brother bruce in a t w exclusive report we hear from this man who says he was part of a team ordered to kill opposition politicians in the country 20 years ago also on the program protests over indias new citizenship lol spread demonstrators in the capital delhi towards vehicles into