Galileo Galilei first described 'the principle of relativity' in 1632 in his 'Dialogue Concerning the Two Chief World Systems'. Galileo used the example of a ship traveling at constant speed, without rocking, on a smooth sea; any observer doing motion experiments below the deck would not be able to tell whether the ship was moving or stationary.
This lead Galileo to state that the laws of physics are the same in any system that is moving at a constant speed in a straight line, regardless of its particular speed or direction. Hence, there is no absolute motion and no absolute rest.
This was a far reaching and quite visionary insight by Galileo, more than two centuries ahead of his time. The principle is sometimes called 'Galilean relativity'.
Sir Isaac Newton (1687)
Galileo's work provided the basic framework for Sir Isaac Newton's three laws of motion, published in his monumental 1687 work, now known as the 'Principia'. Hence Galileo's relativity principle is also sometimes, perhaps wrongly, called 'Newtonian relativity'".
Newton's three laws of motion can be briefly stated as:
(i) An object at rest tends to stay at rest and an object in uniform motion tends to stay in uniform motion, unless acted upon by an external force.
(ii) The acceleration of an object is directly proportional to the magnitude of the force acting on it and inversely proportional to its mass.
(iii) For every action there is an equal and opposite reaction.
Significant as these laws are, in a way they regressed backwards when compared to Galilean relativity. Newton stated his laws to hold in 'absolute space', meaning that there must be absolute motion and absolute rest. This was partially caused by the view of the time that in empty space light moves at a constant speed through an invisible medium called the 'aether'.
Galileo did not believe in absolute motion, but like Newton, he believed in a universal time that is the same for every uniformly moving reference system (called an 'inertial frame'), regardless of its velocity.
Albert Einstein (1905)
On the matter of universal time, Einstein differed from both Galileo and Newton. In his groundbreaking 1905 paper, 'On the Electrodynamics of Moving Bodies', he abandoned universal time and postulated that every inertial frame has its own unique time.
Einstein restated Galileo's principle of relativity, where the laws of physics are the same in every inertial frame, regardless of its particular speed or direction. Einstein's 1905 insight extended Galilean relativity in one crucial aspect: the speed of light in free space (symbol c) is the same in every inertial frame of reference, irrespective of its movement.
Incidentally, Galileo also thought that the speed of light is the same in every inertial frame, but that's only because he reasoned that light's speed was near infinitely large. If you take Einstein's equations of special relativity and set the speed of light to infinity, you end up with Galileo's principle of relativity. So in a way, Galileo and Einstein were closer in their principles of motion than what Newton and Einstein were.
Newton (like Einstein) knew that light had a finite, measurable speed. Newton did however (wrongly) hold that the speed of light is only constant in absolute space, meaning that it must have different values relative to moving observers. If Newton has been right, the speed of light would have been different in different directions inside a moving inertial frame. This has been ruled out by experiments.
Einstein postulated that the relative nature of motion and of time dictates that all inertial frames will measure the same constant speed of light in all directions. Experiments have confirmed this view. Einstein's principles of special relativity can be briefly summarized as follows:
i) There is no observable absolute space or absolute motion.
ii) There is no universal time. Every inertial frame has its own time.
iii) The laws of physics are the same in every inertial frame.
iv) The measured speed of light is independent of relative motion.
These four principles imply that time and distance measurements differ in various inertial frames. In general, if two observers are moving relative to one another, they will disagree on the distance between two objects and also on the time that it takes light to travel that distance. This is the essence of Einstein's special theory of relativity.
Gravity: Newton (1687) - Einstein (1916)
Einstein's general theory of relativity of 1916 extended his special theory to include gravity, essentially replacing Newton's theory of universal gravitation, as described in his 'Principia' of 1687. When the gravitational field is weak and the speeds are very small compared to the speed of light, Newton's theory of gravity is accurate enough for all practical purposes.
Einstein's theory of relativity only becomes a requirement when speeds are significant fractions of the speed of light and/or the gravitational fields are thousands of times stronger than what we experience here on Earth. Such conditions are observed near neutron stars and black holes, but that's another story.
The word ?remediation? is very important in the work my colleagues and I do with families affected by autism and other neuro-developmental disabilities, but it is a word that is unfamiliar to many people. I thought I would take a moment this week to talk about what remediation means in general, and specifically in the realm of autism.
Let's start with some basic dictionary definitions: Remediate (verb)?To remedy a problem Remedial (adjective)?Intended to correct or improve one's skill in a specific field; therapeutic, corrective, restorative Remediation (noun)?Use of remedial methods to improve skills; the act or process of correcting a deficiency
Dr. Steven Gutstein's definition of remediation: Correcting a deficit to the point where it no longer constitutes and obstacle
My definition: Work ON something, not just around it
Whether you are a parent or professional, it is critical to understand what remediation is, and the distinction between remediation and compensation. Perhaps the most common application of this distinction is in the area of reading problems. If a child is diagnosed with a reading disability, we typically apply remediation approaches to help them learn to read. At various points we may use compensations, such as books on tape, to support them. However, our goal is to remediate, or correct, the problem that is preventing them from reading so they can become functional readers. In my professional experience, I have yet to come across a situation where adults believe that if an 8 year old child is not yet reading, that we should just compensate for that and give them books on tape to listen to for the rest of their lives. Remedial efforts are taken to get to the root of the problem and overcome the issues that are preventing successful reading.
Now take this same concept and apply it to individuals on the autism spectrum. By definition they are struggling in many areas: socialization, communication, thinking flexibly, and the list goes on depending on the person. What approach do we usually take to these deficits? By and large, we take a compensation approach. We find ways to work around these problems so that the students fit into the mold of what we do at home and in school everyday. Our main motivation becomes applying strategies that help them exhibit what we consider to be ?typical? behaviors ?sit appropriately in the classroom or at church, learn academic skills, play on the playground equipment, wait in line without becoming upset, greet others when we see them, etc. While we may also look for ways to support their communication and to improve their relationships with others, we do this on a very surface level without really understanding the obstacles that create those problems in the first place. And, because we don't really understand the root issues that create these problems, we resort to compensation techniques rather than remediating the root causes.
When you look at the history of treatments in the field of autism, it has been primarily about compensation. While research on the brain and autism has continued to move forward and provide us new information, our treatment approaches have stagnated. The methods we were using 30 years ago are still the methods being used today, despite the fact that we have a whole host of new information available to us. We now have the capacity to take what we know about the disorder of autism and how it impacts brain function, and develop new techniques and approaches that move beyond compensation and actually work to remediate (correct) the primary features of the disorder. This is one of the exciting things about newer approaches such as the Relationship Development Intervention (RDI)? Program, which focuses on remediating, rather than just working around, the core deficits we see in individuals with autism and other neuro-developmental disorders.
It is time to move beyond thinking about treatment as merely capitalizing on strengths, and begin thinking about how to strengthen areas of weakness. Research has shown us that autism is primarily a disorder of connectivity in the brain?with some portions over connected and others under connected. What is so exciting about this is that we know that neural connectivity can change throughout the lifespan. The human brain has an enormous capacity for developing new connections and changing the patterns of connectivity when given the right types of stimulation. This is what allows us to look at autism treatment in a new light. It cannot be merely about strengthening the areas that are already strong. Effective education and treatment must be focused on building new connections in the areas where connectivity is deficient. This is the essence of remediation.
Both Burt Jordaan & Horizons are contributors for EditorialToday. The above articles have been edited for relevancy and timeliness. All write-ups, reviews, tips and guides published by EditorialToday.com and its partners or affiliates are for informational purposes only. They should not be used for any legal or any other type of advice. We do not endorse any author, contributor, writer or article posted by our team.
Burt Jordaan has sinced written about articles on various topics from Education Toys, Aging and Education. Burt Jordaan writes relativity and cosmology for non-scientists. Take a look at popular articles and "lightly technical" downloads, freely available by clicking here: =>. Burt Jordaan's top article generates over 5400 views. to your Favourites.
Horizons has sinced written about articles on various topics from Children, Fitness and Parenting. Autism specialist Courtney Kowalczyk, of the Horizons Developmental Remediation Center, provides practical information and advice for families living with autism and other developmental disabilities. If you are ready to reduce your stress level, enrich yo. Horizons's top article generates over 9900 views. to your Favourites.