or a renting of the thin membrane that separates this world from the other competing worlds next door. i so want to open my eyes! with your eyes closed, try to form an image in your mind of the person sitting opposite you. don't look. don't check if they have closed their eyes. ok, this performance is aimed at couples but ignoring that minor issue, it's all about placing yourself in the story. double is the latest show from darkfield radio. its recent sound—only productions took place in pitch black shipping containers. now, though, it is possible via an app and a pair of headphones. so when we were working with creating these experiences at home, we still wanted it to feel like a live experience. so one of the important elements of that is that it is a timed show — something that happens at a certain time — so there is some feeling of community about it, even though people are sat

in their different homes. the main reasons that i think that there is a lot more interest in binaural sound now because of vr and of this increasing interest in immersive experiences that placing at the centre of a narrative. i'm kind of on edge because i wonder whether something... something that will make us jump. chuckles. male voice: two people who have known each other for however many years sit on either the side of a table. one of them has been replaced by a demon whose intentions are unclear and unlikely to be benign, and the other is planning a murder. planning a murder? is that you? i don't know! one of us has turned into a demon and the other is planning the murder. we both sound a bit dodgy. plate smashes.

what was that? i have no idea. much like the biannual sound recordings we've seen on the show before, it's recorded using a binaural sound head, shaped like a human. in both ears are microphones. you treat this head as if it were the audience members who is going to be then listening to the performance, so every — everything that the head hears is — will be from the perspective of the future audience member listening with headphones. and one of the things that binaural recordings do better than any real—time audio spacialisation is proximity, so we are also developing some other tech elements to include live microphones with the audio of the microphone spacialised, speech recognition and a few other things that will allow us to increase this interactivity. male continues speakingzw didn't take long for the right moment to come. clock ticks softly. because opposite me, the demon has its eyes closed. and so, i stabbed it. cutlery clangs on a plate.

and now that the demonic copy is disposed of... oh god! lara laughs. ..our real partner can come back. # i love you with my heart. this is pretty freaky! # i love you with my mind. it's whispering in my ear! no! i don't like it! 0h! and open our eyes. goodness, that but quite bizarre! oh, that was a bit of fun! conceptually, i thought it was brilliant, but i wasn't sure about the storyline because i didn't actually want to murder you. and even though it sounded good, i think we probably would have both benefited from over—ear headphones. true. what's interesting though is because they asked the two people to face each other, they really can make things sound like they come from a specific place in the room because they can send one person a sound in their right ear and they send the other person

a different feed where the sound is in their left ear, so you can both agree that the sound happened over there. really interesting concept, i have to say. now onto the great barrier reef, wonder of the world, the largest living structure on the planet. at over m00 miles long, it's so big that you can see it from space! but as you probably know, it is under threat. rising water temperatures and a changing environment cause the coral to go white, to bleach, and the reef has just undergone its third mass bleaching event in the past five years. this time, for the first time, white, stressed coral has stretched from one end all the way to the other. while cyclones and climate change pose huge threats to the reef, there are other factors, too. so nick kwek‘s been finding out the great barriers

to the reefs survival. sugar, a billion—dollar business to australia. almost all of its cane is grown here in queensland, with the great barrier reef right on its doorstep. when it comes to conserving the reef, a lot of work is being done out at sea, but there is also stuff happening right here at sugarcane farms like these, which are dotted all around the tropical coast. it is the run—off from these sugarcane farms, the pesticides, the herbicides, that are posing to be a huge threat to the future health of the great barrier reef. chris and belinda have developed smart water sensors that remotely measure nitrate levels in farm lagoons. nitrate can lead to more algae build—up and less coral diversity out on the reef. that's where the light shines through and that's where you get your reading from. their system, including a bunch of sensors and a computer in a waterproof box, help them remotely secure more accurate readings around the clock and, crucially, gauge the effects of

specific rain events. we might not have a lot of nitrogen leaving every paddock on every farm, but all it really needs is a little bit over a large area of land. those marine systems, they have not evolved with high nitrogen levels, so once that changes a little bit, you change the balance. robotic voice: enable screen. one solution could be this herbicide—spraying drone that zones in from above and targets hard—to—reach weeds, thus greatly reducing the amount of chemical spread across a field. often here, especially in the wet tropics, you cannot get back onto the paddock, so it is too wet to be able to get onto. or, as we have with sugarcane, it becomes too large, so the only way to get any product back onto it is to do it with an aircraft of some kind. the 06! drone has four radar sensors on board so it can get close enough to crops without crashing, and the nozzles have

been specifically designed to form just the right amount of liquid so droplets don't blow off into the wind. airborne contraptions are helping the reef in other ways. these three little bumps just there? yeah. that means that this is live coral. right. so you can inferjust from the shape of the wave? yeah. doctor karenjoyce uses drones equipped with sensors like spectrometers to capture detailed information unseen by the human eye. it measures the way light is reflected or absorbed. so, for example, we see trees as green because they reflect green light. different things on the reef reflect light differently as well. that helps us to understand the types of things we have on the reef but also how healthy they are. you just realise how small an area the drone can capture. so that would be like 15 minutes' work to do just that little bit there. and this only represents one of 3,000 of the reefs of the great barrier reef. to better understand the scale

and complex ecosystem of the reef, i have come to the epicentre of tropical marine research — the australian institute for marine science. behold, the seasim! one of the most advanced reef replicators on the planet. 33 tanks, more than 140 pumps, and over 42 kilometres of piping, all controlled with custom tech. and of course, ijust had to have a nosy behind the scenes. the bits and pieces you see along the back wall here, they're what control our ph. they provide dynamic active control of the processes occurring in the tank. and that means we get much, much better control, much tighter control of our seawater, so the conditions are more like what we actually see out on the reef. they've have got taps, tubes, a orange snake! musical sting. this enables us to control our temperature within plus or —0.1

of a degree. we can create profiles, where they be seasonal or daily. we can control salinity, so replicating freshwater plumes. we can replicate contaminants, whether they be nutrients or pesticides, insecticides — a whole range of different parameters. the seasim's able to precisely replicate the conditions of the great barrier reef as it's found in nature, but it's also able to look into the future. what will the reef look like in, say, 50 or 100 years from now? we're looking at those mechanisms that make corals more thermally resilient. this is not a solution. the solution is dealing with climate change and the carbonisation of the economy. we're just looking at ways of assisting this to enable those corals to survive, until we find a solution to that bigger issue. scientific facilities, drones, monitoring sensors — these are just some of the many efforts to importantly buy time for the reef. while seismic shifts are required to truly preserve this natural phenomenon,

small actions can lead to big change. fascinating stuff! that was nick in australia, and that's it from us for this week. as ever, you can keep up with the team on social media throughout the week on youtube, instagram, facebook and twitter at @bbcclick. thanks for watching and we'll see you soon. bye— bye. hello there. scotland, northern ireland didn't fare too badly on friday with some good spells of sunshine around, some pleasant sunset scenes as well. but for england and wales, it really was pretty atrocious. wet and windy — all courtesy of storm alex — and it looks like all areas willjoin in with the heavy rain this weekend, including

scotland and northern ireland. could cause some transport disruption, some flooding in places, and the winds will be quite a feature too. so for saturday, it looks thoroughly wet to start the day across much of england and wales, eastern scotland, that rain also drifting a little bit further westwards at times. but meanwhile, it will be clearing a little bit from the south—east, so here, we could see some brightness into the afternoon, but it stays windy. south wales into south—west england, those temperatures pretty disappointing — the low teens for most of us, could see 16 in the south—east. but it's the rainfall amounts we are most concerned about this weekend. saturday into sunday morning, amber warnings issued for parts of wales, the south—west of england and also for the east and north—east of scotland. areas here, certainly over the high ground, could see in excess of two inches of rain, so flooding is likely to be an issue here. as we move through saturday night then, that rain really piles its way westwards, affecting northern ireland as well. winds will be quite strong across the south—west. temperatures a little bit lower than what we had for the previous night — typically around 9—10 degrees. now, this new area of low

pressure will be sitting right across the uk as we head on into part two of the weekend. it will be sending bands of cloud and rain around the country, mainly around its periphery, where we will also see the strongest of the winds — gale force winds at times here — but in the centre of it, winds not quite as strong. and we should see some sunshine and that will set off a few heavy, maybe thundery showers. and again, those temperatures pretty disappointing — in the low teens for most. as we move out of sunday into monday, our area of low pressure begins to fill somewhat, begins to weaken a little bit, but it is still going to be enough to generate showers or longer spells of rain, certainly around the edges. fairly strong winds, too, though those winds will continue to ease down. central areas will see the lightest of winds with some sunny spells through monday afternoon, but that could set off some heavy, maybe thundery showers again. temperatures again low teens for most but we could make 15 or 16 in the south—east, given some sunshine and light winds. but it remains unsettled as we head through the new week, certainly for england and wales, with a high chance of heavy showers

and sunny spells.

this is bbc news. welcome if you're watching here in the uk, on pbs in america or around the globe. i'm james reynolds. our top stories: president donald trump has been taken to hospital for treatment after being diagnosed with coronavirus. he left the white house unaided, wearing a mask. on twitter he said he was doing well. i am going to walter reed hospital. i think i am doing very well, but we are going to make sure that things work out. the first lady is doing very well. so thank you very much. i appreciate it. i will never forget it. thank you. he's already been treated with an antibody cocktail and vitamins. his doctors earlier said he was fatigued but in good spirits. we'll look at the possible health risks the president is facing.