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Sten's Space Blog Search Primary Menu Skip to content Cosmology Gravity Questions and Answers Space Travel The Astronomy Cafe Videos Weird Stuff Who is this guy? Search for: Uncategorized Silent Earth November 19, 2019 StenBlog Noise pollution is a serious matter that can affect not only how well you sleep at night, but also your health and even psychological state. None of this should surprise you, but as our planet becomes more urbanized, the expanding cloud of man-made noise from jets, traffic and even leaf-blowers can penetrate even remote forests and habitats. Just out of curiosity, I have created a citizen science project that you can download to your phone from your app store and help me map, not the noisiest places on this planet, but the quietest places. The project can be found by downloading from your store the app called ‘Anecdata’. It will ask you to register by entering an email address, a username and your own private password. Once registered, scroll down the project page and join the one called ‘Silent Earth’. You should also join the Facebook group called ‘The Silent Earth Project’ because I post updates there and tips for taking data, as well as interesting results along the way. https://www.facebook.com/SilentEarthProject This is what the project banner looks like on your phone In time, I will be using this blog space to include article of interest on noise pollution and some of our results as we get more areas covered. Here is what you need to do to get going. Check out the national map by the National Park Service to see how your area ranks https://earthsky.org/earth/map-shows-loudest-quietest-places-in-u-s Step 1: Tap the bar that says ‘+Observe’ on the project window Step 2: Tap the bar that says ‘Measure’ and click ‘OK’. Remain quiet for a few seconds. Step 3: Tap the check boxes that apply to you and your location Step 4: Tap the ‘save’ tab at the upper right of the screen to record your data. Don’t be shy!! Make as many measurements as you like but certainly more than one!!! Also, if it seems noisy where you are, say above 50 decibels (dB) walk around your neighborhood or town (or use a bike or car) to find a place that is quieter than what you just measured. Numbers in the 40s are very typical of suburban locations but numbers in the 30s are exceptionally quiet and what you would find in rural locations where there is little traffic, jet, plane or other man-made noises. One of the quietest places I have encountered is deep inside Skyline Caverns in Virginia where readings in the high-20s were encountered! citizen science noise pollution Brain Research , Physics , Time What is ‘Now’? June 29, 2019 StenBlog What is the duration of the present moment? How is it that this present moment is replaced by ‘the next moment’? Within every organism, sentient or not, there are thousands of chemical processes that occur with their own characteristic time periods, but these time periods start and stop at different times so that there is no synchronized ‘moment’. Elementary atomic collisions that build up molecules take nanoseconds while cell division takes minutes to hours, and tissue cell lifespans vary from 2 days in the stomach lining to 8 years for fat cells (see Cell Biology ). None of these jangled timescales collectively or in isolation create the uniform experience we have of now and its future moments. To find the timescale that corresponds to the Now experience we have to look elsewhere. It’s all in the mind! A variety of articles over the years have identified 2 to 3 seconds as the maximum duration of what most people experience as ‘now’, and what researchers call the ‘specious present’. This is the time required by our brain’s neurological mechanisms to combine the information arriving at our senses with our internal, current model of the ‘outside world’. During this time an enormous amount of neural activity has to happen. Not only does the sensory information have to be integrated together for every object in your visual field and cross connected to the other senses, but dozens of specialized brain regions have to be activated or de-activated to update your world model in a consistent way. In a previous blog I discussed how important this world model is in creating within you a sense of living in a consistent world with a coherent story. But this process is not fixed in stone. Recent studies by Sebastian Sauer and his colleagues at the Ludwig-Maximilians-Universität in Munich show that mindfulness meditators can significantly increase their sense of ‘now’ so that it is prolonged for up to 20 seconds. In detail, a neuron discharge lasts about 1 millisecond, but it has to be separated from the next one by about 30 milliseconds before a sequence is perceived, and this seems to be true for all senses. When you see a ‘movie’ it is a succession of still images flashed into your visual cortex at intervals less than 30 milliseconds, giving the illusion of a continuous unbroken scene. (Dainton: Stanford Encyclopedia of Philosophy , 2017). The knitting together of these ‘nows’ into a smooth flow-of-time is done by our internal model-building system. It works lightning-fast to connect one static collection of sensory inputs to another set and hold these both in our conscious ‘view’ of the world. This gives us a feeling of the passing of one set of conditions smoothly into another set of conditions that now make up the next ‘Now’. To get from one moment to the next, our brain can play fast-and-loose with the data and interpolate what it needs. For example, it our visual world, the fovea in our retina produces a Blind Spot but you never notice it because there are circuits that interpolate across this spot to fill-in the scenery. The same thing happens in the time dimension with the help of our internal model to make our jagged perceptions in time into a smooth movie experience. Neurological conditions such as strokes, or psychotropic chemicals can disrupt this process and cause dramatic problems. Many schizophrenic patients stop perceiving time as a flow of linked events. These defects in time perception may play a part in the hallucinations and delusions experienced by schizophrenic patients according to some studies. There are other milder aberrations that can affect our sense of the flow-of-time. Research has also suggested the feeling of awe has the ability to expand one’s perceptions of time availability. Fear also produces time-sense distortion. Time seems to slow down when a person skydives or bungee jumps, or when a person suddenly and unexpectedly senses the presence of a potential predator or mate. Research also indicates that the internal clock, used to time durations in the seconds-to-minutes range, is linked to dopamine function in the basal ganglia. Studies in which children with ADHD are given time estimation tasks shows that time passes very slowly for them. Because the volume of data is enormous, we cannot hold many of these consecutive Now moments in our consciousness with the same clarity, and so earlier Nows either pass into short-term memory if they have been tagged with some emotional or survival attributes, or fade quickly into complete forgetfulness. You will not remember the complete sensory experience of diving into a swimming pool, but if you were pushed, or were injured, you will remember that specific sequence of moments with remarkable clarity years later! The model-building aspect of our brain is just another tool it has that is equivalent to its pattern-recognition ability in space. It looks for patterns in time to find correlations which it then uses to build up expectations for ‘what comes next’. Amazingly, when this feature yields more certainty than the evidence of our senses, psychologists like Albert Powers at Yale University say that we experience hallucinations ( Fan, 2017 ). In fact, 5-15% of the population experience auditory hallucinations (songs, voices, sounds) at some time in their lives...