Ignore double \newline on page break

Question

When I want two paragraphs of text to be separated by an empty line in between, I use:

\newline
\newline

However, I would like that extra empty line to be ignored if it happens that the page breaks right where it would be inserted - such that there is no empty line starting a new page.

I am new to Latex, but it seems to me that people don't want to leave empty lines between paragraphs, but just have the next one indented as is Latex default.

Is there a natural implementation for the 'wide paragraph break' such that Tex behaves as I want it to on pagebreaks?

I read about parskip, but I don't want this behavior for every new paragraph, just for some.

Answer 1

LaTeX offers certain sizes of vertical skips given by \smallskip, \medskip, and \bigskip. These can be invoked for a local change in the vertical spacing, unlike \parskip<length>, which will apply to all subsequent paragraph breaks.

If these pre-packaged sizes are not suitable for your needs, you can use \vspace{<length>} instead. As long as the * version of \vspace is avoided, the space will not be applied at a page break.

You will see that \bigskip has no effect at the top of page 2. The same comment is true of the other vertical skips.

\documentclass[letter]{article}
\usepackage[pass,showframe]{geometry}
\begin{document}
text

text

\smallskip 
text

\medskip
text

\bigskip
text

\vspace{6.4in}
some other text on a new line

\bigskip
x
\end{document}

One should keep in mind that \newline operates within a paragraph, whereas these skips operate between paragraphs. In this sense, the use of \noindent may also be useful with the proposed technique, depending on the OP's application.

Answer 2

vertical space is always dropped at a page break, \newline\newline is the same as

\newline 
please ignore this text
\newline

that is, it does not end the paragraph or add vertical space, it simply extends the current paragraph by a spurious empty line (and latex will warn about underful hbox). As the white area is a (empty) line of text not a vertical space it is preserved at the top of a page just as any other line is preserved.

If you want a style that marks paragraphs by no indentation and vertical space then that can be set by the docuemnt class, or for the standard document classes which do not have that option use

\usepackage{parskip}

If you only want vertical space for some paragraphs then usually that is implied by whatever structural markup you ate using so for example \begin{quote}...\end{quote} will add vertical space, as will markup for theorems etc.

If you really want a one-off space then end the paragraph with a blank line as usual and then add extra space with \vspace that will be dropped at a page break (the variant \vspace* produces a space that is not dropped.)

para...

\vspace{10pt}
new para

Answer 3

Use

\documentclass{article}

\newcommand{\nl}{\newline\vspace{1cm}}
\begin{document}
Then we map spin operators to spinless fermionic creation and annihilation operator by Jordan–Wigner transformation.
\nl
The Hamiltonian obtained is closely related to Kitaev's one-dimensional p-wave superconductor, a model for a topological superconductor in one dimension.

And use \nl where you were using \newline.

Enter any size in place of 1cm like 12pt.

Use \newcommand{\nl}{\newline\vspace{1cm}\par} if you want indentation.