Academics are challenging one prominent theory being taught in a growing number of schools across American.

It's a discovery that appears to challenge the long-held theory that exercise can strengthen bones and offset some of the risks of dietary inadequacies.

It also challenges the classical attachment theory that has dominated parenting advice for decades.

There's no way to prove or disprove their theory.

This disproved the theory that good teams win when they are not playing well.

His flat performance against the Swiss side did little to disprove the theory that all is not well.

Economic theory is clear on the issue.

If planning is so inefficient, and discredited in economic theory, why does it persist?

More importantly, economic theory has become a branch of political ideology.

In time, ' modern linguistic theory, in its turn, became the seedbed for high-level computer languages'.

The aim has always been, then, to reduce the power of linguistic theory while at the same time being able to cover all the relevant facts.

In this study we consider proposals made by linguistic theories and psycholinguistic models to derive two predictions for the processing of grammatical words compared to lexical words.

His biographical writings have never been properly integrated with his poetic and linguistic theories.

Management theory suggests that being the most competent person in a group may not be great for the group if that person rubs others up the wrong way, or works in a way that clashes with fellow members of his group.

A lot of management theory was very mechanistic and quantitative then.

Management theories have come and gone, and never more rapidly than in the 1990s.

But Marxist theory tended to view " capitalist" planning in a negative light.

Midnight discussions about Marxist theory and Buddhism were right up his street.

Such change is to be expected, according to Marxist theory.

The links with modernization theory are numerous.

Indeed, the emphasis on internal factors, economic, social or cultural, was to characterize most modernization theory.

Such a trend towards dependency has figured largely in the responses which modernization theory has excited.

They feel they may be about to make sense of the huge complexities thrown up by the revolutions of quantum and relativity theory.

His friend had been working lately on relativity theory.

Modern relativity theory has placed a number of more specific obstacles in the way of a tensed metaphysics.

He knew that his 1905 special relativity theory applied only to the relationship between a body at rest and a body moving at a constant velocity.

Any scientific theory is open to being superseded by a better one as research progresses.

More plausible scientific theories have been proposed in recent times.

If scientific research yields observations that are inconsistent with scientific theories, then one or the other must be wrong.

I was testing the theory that surfing is fun for all ages.

A group of 35 cancer patients test the theory that singing may help people battle the disease by forming a choir.

The history series is about doctors who became their own guinea pigs to test experimental theories.

Now if these theories are correct, there are at least two important implications.

We can only wait to hear which theory is correct, if any.

If this theory is correct, it will transform our ideas about space and time.