These words are in practice synonyms, but suggest different ways in which we consider what's going on.

• "Construct" suggests thinking of a FREDKIN gate as a subroutine, which you realise as a composition of more primitive operations.

• "Simulate" suggests the idea that there is some model (eg. conservative reversible computation) for which FREDKIN is a primitive, and which you are realising by other operations in some other model (eg. quantum computation, or reversible but not necessarily conservative computation) in which it is not a primitive.

The second viewpoint is particularly useful when you consider operations which are being realised using a protocol which succeeds only under certain circumstances, or using a protocol which is only realises an operation up to some probability of error or up to some precision.

The words "construct" and "generate" are in practice synonyms when it comes to transformations, but suggest different ways in which we consider what's going on.

• "Construct" suggests thinking of a FREDKIN gate as a subroutine, which you realise as a composition of more primitive operations.

• "Simulate" suggests the idea that there is some model (eg. conservative reversible computation) for which FREDKIN is a primitive, and which you are realising by other operations in some other model (eg. quantum computation, or reversible but not necessarily conservative computation) in which it is not a primitive.

The second viewpoint is particularly useful when you consider operations which are being realised using a protocol which succeeds only under certain circumstances, or using a protocol which is only realises an operation up to some probability of error or up to some precision.

These words are in practice synonyms, but suggest different ways in which we consider what's going on.

• "Construct" suggests thinking of a FREDKIN gate as a subroutine, which you realise as a composition of more primitive operations.

• "Simulate" suggests the idea that there is some model (eg. conservative reversible computation) for which FREDKIN is a primitive, and which you are realising by other operations in some other model (eg. quantum computation, or reversible but not necessarily conservative computation) in which it is not a primitive.

The second viewpoint is particularly useful when you consider operations which are being realised using a protocol which succeeds only under certain circumstances, or which is only realised up to some probability of error or up to some precision.

These words are in practice synonyms, but suggest different ways in which we consider what's going on.

• "Construct" suggests thinking of a FREDKIN gate as a subroutine, which you realise as a composition of more primitive operations.

• "Simulate" suggests the idea that there is some model (eg. conservative reversible computation) for which FREDKIN is a primitive, and which you are realising by other operations in some other model (eg. quantum computation, or reversible but not necessarily conservative computation) in which it is not a primitive.

The second viewpoint is particularly useful when you consider operations which are being realised using a protocol which succeeds only under certain circumstances, or using a protocol which is only realises an operation up to some probability of error or up to some precision.