THE weird and wonderful world of quantum physics is becoming a spiritual resource, or so an increasing number of people claim. Writers as diverse as the ecotheologian Thomas Berry, the New Age philosopher Ken Wilber, the Sacred Heart Missionary Diarmuid O'Murchu, and the American Evangelical Rob Bell (Features, 12 April) read about the strange things that quarks and bosons get up to, and spot religious resonances.

As the Bishop of Kingston, the Rt Revd Richard Cheetham, argued last week (Comment, 24 May), we need to know more about the relationship between science and religion, as our culture turns increasingly to science as a source of authority and meaning. What might be called "quantum spirituality" is a good case in point. It suggests the need to engage carefully with science, and to respect each discipline on its own terms.

The quantum world is odd. Take the effect known as quantum entanglement. This is when subatomic particles appear to be connected, although they are substantial distances apart. The latest experiments have measured the effect with particles separated by about 100 miles. The phenomenon seems to imply that information can be exchanged instantaneously outside space and time, and this generates a great deal of speculation, from the possibility of Star Trek-like teleporting to human telepathy. For the spiritually inclined, it speaks of a further truth: like entangled particles, we are all linked, and in some sense might be one. 

ANOTHER effect often referenced in this area is the part that observation plays in quantum physics. It is captured in the famous thought-experiment known as Schrödinger's cat. This imagines a cat in a sealed box. It lives if a quantum event does not happen, and dies if one does. A paradox arises because, according to quantum theory, quantum systems exist simultaneously in all theoretically possible states. Technically, it is known as the superposition of states.

Again, the phenomenon is real in the sense that it can be manipulated. Quantum computing may be one result. But it leads to the odd conclusion that Schrödinger's cat is both dead and alive, because the outcomes that would determine its future co-exist.

The paradox can be resolved by appealing to observation, which is to say that observers play a crucial part in quantum processes. The idea is that an observer takes a look, and, in that instant, it is "decided" whether the quantum event is or is not realised. Hence, at the macro level, the cat turns out to be definitely dead or alive. Yet this only compounds the issue, because it could suggest that observers, such as human beings, are required to convert the indeterminate world at the quantum level into the tangible world that we know. 

THE possibility that quantum physics cannot be formulated without reference to such observers has led some physicists to conclude that consciousness and self-consciousness have a purpose in the grand scheme of things. "The universe is 'about' something," Professor Paul Davies writes in The Goldi- locks Enigma (Allen Lane, 2006).

The Nobel laureate Eugene Wigner went a step further. He concluded that consciousness was "an ultimate reality". Again, to the spiritually inclined, this sounds remarkably like confirmation of another great truth, the existence of God.

Other parts of quantum theory appear to hold similar spiritual possibilities. The so-called fine tuning of certain physical constants to make things right for life has been taken as implying that the universe is, in some sense, "for us". There is, however, less justification for the uncanny resonance with religious beliefs. Two significant problems stymie such links. 

FIRST, alternative explanations are available. Take the issue of observers' apparently being required to bridge the gap between the microscopic and the everyday. It is possible that quantum physics is simply incomplete. The science of today is missing something, and so it only seems as if observers are needed. In the future, however, more details will become apparent, and the appeal to observers may not be required. Einstein, for one, felt that this was more likely.

Second, it is unclear just what quantum physics tells us about the way the cosmos actually is. Strange to say, but although it is arguably the most successful theory in science, making predictions of extraordinary precision and lying at the heart of much modern technology, there is still no consensus about how to interpret it at a fundamental level.

A recent poll of physicists and philosophers, conducted by Professor Anton Zeilinger, a physicist who is known for his work on quantum entanglement, reports that the favourite way of understanding what quantum physics means is known as the Copenhagen interpretation. Devised by such luminaries as Niels Bohr and Werner Heisenberg, it says that, in spite of the success of the science, it tells us nothing about the way the world is in itself. Objective truth lies permanently behind a veil of ignorance. The paradox of Schrödinger's cat simply highlights what we cannot know, not what we might infer.

The upshot is that all the spiritual speculations are just that: speculations. The science confirms nothing for sure. Appealing to the physics as a source of authority is a mistake. As the Revd Dr John Polkinghorne, the former physics professor who was later ordained priest, has remarked: "Physics is showing the world to be both more supple and subtle, but you need to be careful."

Whether or not the Copenhagen interpretation is itself right, or whether other possibilities might be better, is not likely to be decided any time soon. In the mean time, it seems sensible to be wary of quantum spirituality, when the science is being asked to do more than provide vivid analogies for spiritual realities.

Spirituality should trust its own sources of authority. It is a mistake to reach out to a science that is undecided, and likely to change remarkably fast.

Mark Vernon is the author of Love: All that matters (Hodder).