Date Published:

How fast?

How long does it take the light to get from the Sun to the Earth?

A:  No time all.  You will hear the answer ‘8 and a half minutes’ but that is from our perspective on Earth.  From the perspective of the light, it takes no time at all!  So it takes the light no time, be we see it as taking over 8 minutes.

Relativity is that all observations are relative to the perspective of the observer.

The point is that time itself is relative to the observer. Acceleration changes the perspective of an observer, so as an observer changes speed, time changes. For perspective to change significantly, you have to be travelling at incredible speed, as the change is determined by your speed as a fraction of the speed of light.  The light itself, in the above example, is actually travelling at infinite speed from the perspective of light.  But relativity means time distorts and any observer not also travelling at the speed of light, will observe the light travelling at the fastest speed anything will appear to be travelling at, the speed of light.

Yes, you can go faster than 300,000km/s (lightspeed), it just doesn’t look that way to others.

You may read that the approximately 300,000km/s (the speed of light) is the fastest speed there is. In reality this depends on point of view).  You will also read that if you travel fast enough time will pass more slowly and if you travel the over 4 light years to the nearest star fast enough, that although it will still take over 4 years on Earth, only 1 year will pass for you, and fellow travellers.  So you would then have travelled over 4 light years in 1 year of your time. If you divide distance travelled by time you get 4 light years per year- or 4x the speed of light at 1,200,000km/s.  The trap is that, for someone who stayed back on earth, over 4 years will have passed, so they will see you as having travelled only slightly below the speed of light.

But for you, the traveller, it is possible to start accelerating and just keep on accelerating at constant acceleration with everything appearing normal. You could keep accelerating to 1 times speed of light, 2 times, 4 times and even faster.  It is those that do not come for the ride who will see your speed as just getting closer and closer to the speed of light, you never reaching the speed of light.

This is not the deepest analysis, but was produced in response to a specific question.

Science & Philosophy

RCS – The SMS successor and blue bubbles vs green culture war.

The world and usage of SMS has moved on since the introduction in 1992, and the system lacks many features now seen as essential including, even the ability to see if a message has been received.

Apple has its own proprietary “iMessage” SMS/MMS successor for communication between iPhones within the Apple walled garden and the bubble wars, Facebook has its own messages system and has “What’s App”, but is there room for a true SMS successor that is not a walled garden fully controlled by one technology company to create division into “tribes”, and instead is able to connect all devices just like the original SMS system?

RCS is simple to enable and is the best messaging solution for Samsung and other Android phones and to end culture wars and walled gardens.

A different perspective: Humans maybe the greatest threat to life on Earth but also the only hope.

The title ‘one finite planet’ can be mistaken to be yet another proclamation of how we live on this amazing planet which could even be unique, and we humans are foolishly placing it all at risk. Boring.

No. Instead, the perspective is we are living on a planet that is naturally hostile to humans, where nature dictates only a limited total amount of life, can only exist for a limited time, and that time is almost at an end. When seen from this perspective, even the environment mission changes from just not interfering, to the more complex task of tackling the challenge of overcoming nature, while yes, quite importantly, not bringing life to an early end in the process.

Surprise, Shortest day ever recorded: Not just the solstice, but climate change?

The first ‘fun fact’ is that while everyone knows how the length of daytime and nigh time vary throughout the year, it may come as a surprise to realise the length of the entire day, also varies. Partly because, second fun fact, the a day is a longer than one rotation of the Earth, which lead to the third fun fact: we just had the shortest total day ever recorded.

WordPress.com to the Next Level: Plugins, Elementor, CoBlocks?

Something completely different. A discussion on how this site is hosted: on wordpress.com.

Anyone who has started a “blog” or other site on wordpress.com, may get to wonder, what are the options for upgrading the website? What is the value of the free, personal or premium plans and beyond? What real world benefits are there, and, alternatively, what would you lose and/or gain from moving away from wordpress.com. This is a page discussing being in that situation. If you are not considering having a website, it may be of little interest.

Images, Making Animated GIFs & Solving colour problems.

This is part of series of pages I will be adding on things I have learnt as part of building this website, and I will soon try and enable following by topic (when I get this page working), so people can separately select notification on building websites and/or population or other issues, without being notified of things outside their interest. Standby for that update.

Meanwhile this page provides general help on making an animated GIF for a series of images, specific help on a challenge with animated GIFs, and a list of sites with free images as a resource for those building images.